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UEFI

Unified Extensible Firmware Interface (UEFI, or as an acronym) is a specification that defines the architecture of the platform firmware used for booting the computer hardware and its interface for interaction with the operating system. Examples of firmware that implement the specification are AMI Aptio, Phoenix SecureCore, TianoCore EDK II, InsydeH2O. UEFI replaces the BIOS which was present in the boot ROM of all personal computers that are IBM PC compatible, although it can provide backwards compatibility with the BIOS using CSM booting. Intel developed the original Extensible Firmware Interface (EFI) specification. Some of the EFI's practices and data formats mirror those of Microsoft Windows. In 2005, UEFI deprecated EFI 1.10 (the final release of EFI).

UEFI is independent of platform and programming language, but C is used for the reference implementation TianoCore EDKII.

Contrary to its predecessor BIOS which is a de facto standard originally created by IBM as proprietary software, UEFI is an open standard maintained by an industry consortium.

History
The original motivation for EFI came during early development of the first Intel–HP Itanium systems in the mid-1990s. BIOS limitations (such as 16-bit real mode, 1 MB addressable memory space, assembly language programming, and PC AT hardware) had become too restrictive for the larger server platforms Itanium was targeting. The effort to address these concerns began in 1998 and was initially called Intel Boot Initiative. It was later renamed to Extensible Firmware Interface (EFI).

The first open source UEFI implementation, Tiano, was released by Intel in 2004. Tiano has since then been superseded by EDK and EDK2 and is now maintained by the TianoCore community.

In July 2005, Intel ceased its development of the EFI specification at version 1.10, and contributed it to the Unified EFI Forum, which has developed the specification as the Unified Extensible Firmware Interface (UEFI). The original EFI specification remains owned by Intel, which exclusively provides licenses for EFI-based products, but the UEFI specification is owned by the UEFI Forum.

Version 2.0 of the UEFI specification was released on 31 January 2006. It added cryptography and security.

Version 2.1 of the UEFI specification was released on 7 January 2007. It added network authentication and the user interface architecture ('Human Interface Infrastructure' in UEFI).

In October 2018, Arm announced Arm ServerReady, a compliance certification program for landing the generic off-the-shelf operating systems and hypervisors on Arm-based servers. The program requires the system firmware to comply with Server Base Boot Requirements (SBBR). SBBR requires UEFI, ACPI and SMBIOS compliance. In October 2020, Arm announced the extension of the program to the edge and IoT market. The new program name is Arm SystemReady. Arm SystemReady defined the Base Boot Requirements (BBR) specification that currently provides three recipes, two of which are related to UEFI: 1) SBBR: which requires UEFI, ACPI and SMBIOS compliance suitable for enterprise level operating environments such as Windows, Red Hat Enterprise Linux, and VMware ESXi; and 2) EBBR: which requires compliance to a set of UEFI interfaces as defined in the Embedded Base Boot Requirements (EBBR) suitable for embedded environments such as Yocto. Many Linux and BSD distros can support both recipes.

In December 2018, Microsoft announced Project Mu, a fork of TianoCore EDK2 used in Microsoft Surface and Hyper-V products. The project promotes the idea of Firmware as a Service.

The latest UEFI specification, version 2.10, was published in August 2022.

Advantages
The interface defined by the EFI specification includes data tables that contain platform information, and boot and runtime services that are available to the OS loader and OS. UEFI firmware provides several technical advantages over a BIOS:

 * Ability to boot a disk containing large partitions (over 2 TB) with a GUID Partition Table (GPT)
 * Flexible pre-OS environment, including network capability, GUI, multi language
 * 32-bit (for example IA-32, ARM32) or 64-bit (for example x64, AArch64) pre-OS environment
 * C language programming
 * Python programming using Python interpreter for UEFI shell
 * Modular design
 * Backward and forward compatibility

Processor compatibility
As of version 2.5, processor bindings exist for Itanium, x86, x86-64, ARM (AArch32) and ARM64 (AArch64). Only little-endian processors can be supported. Unofficial UEFI support is under development for POWERPC64 by implementing TianoCore on top of OPAL, the OpenPOWER abstraction layer, running in little-endian mode. Similar projects exist for MIPS and RISC-V. As of UEFI 2.7, RISC-V processor bindings have been officially established for 32-, 64- and 128-bit modes.

Standard PC BIOS is limited to a 16-bit processor mode and 1 MB of addressable memory space, resulting from the design based on the IBM 5150 that used a 16-bit Intel 8088 processor. In comparison, the processor mode in a UEFI environment can be either 32-bit (IA-32, AArch32) or 64-bit (x86-64, Itanium, and AArch64). 64-bit UEFI firmware implementations support long mode, which allows applications in the preboot environment to use 64-bit addressing to get direct access to all of the machine's memory.

UEFI requires the firmware and operating system loader (or kernel) to be size-matched; that is, a 64-bit UEFI firmware implementation can load only a 64-bit operating system (OS) boot loader or kernel (unless the CSM-based Legacy boot is used) and the same applies to 32-bit. After the system transitions from "Boot Services" to "Runtime Services", the operating system kernel takes over. At this point, the kernel can change processor modes if it desires, but this bars usage of the runtime services (unless the kernel switches back again). As of version 3.15, the Linux kernel supports 64-bit kernels to be booted on 32-bit UEFI firmware implementations running on x86-64 CPUs, with UEFI handover support from a UEFI boot loader as the requirement. UEFI handover protocol deduplicates the UEFI initialization code between the kernel and UEFI boot loaders, leaving the initialization to be performed only by the Linux kernel's UEFI boot stub.

Disk device compatibility
In addition to the standard PC disk partition scheme that uses a master boot record (MBR), UEFI also works with the GUID Partition Table (GPT) partitioning scheme, which is free from many of the limitations of MBR. In particular, the MBR limits on the number and size of disk partitions (up to four primary partitions per disk, and up to 2 TB (2 × 240 bytes) per disk) are relaxed. More specifically, GPT allows for a maximum disk and partition size of 8 ZiB (8 × 270 bytes).

Linux
Support for GPT in Linux is enabled by turning on the option  (EFI GUID Partition Support) during kernel configuration. This option allows Linux to recognize and use GPT disks after the system firmware passes control over the system to Linux.

For reverse compatibility, Linux can use GPT disks in BIOS-based systems for both data storage and booting, as both GRUB 2 and Linux are GPT-aware. Such a setup is usually referred to as BIOS-GPT. As GPT incorporates the protective MBR, a BIOS-based computer can boot from a GPT disk using a GPT-aware boot loader stored in the protective MBR's bootstrap code area. In the case of GRUB, such a configuration requires a BIOS boot partition for GRUB to embed its second-stage code due to absence of the post-MBR gap in GPT partitioned disks (which is taken over by the GPT's Primary Header and Primary Partition Table). Commonly 1 MB in size, this partition's Globally Unique Identifier (GUID) in GPT scheme is 21686148-6449-6E6F-744E-656564454649 and is used by GRUB only in BIOS-GPT setups. From GRUB's perspective, no such partition type exists in case of MBR partitioning. This partition is not required if the system is UEFI-based because no embedding of the second-stage code is needed in that case.

UEFI systems can access GPT disks and boot directly from them, which allows Linux to use UEFI boot methods. Booting Linux from GPT disks on UEFI systems involves creation of an EFI system partition (ESP), which contains UEFI applications such as bootloaders, operating system kernels, and utility software. Such a setup is usually referred to as UEFI-GPT, while ESP is recommended to be at least 512 MB in size and formatted with a FAT32 filesystem for maximum compatibility.

For backward compatibility, some UEFI implementations also support booting from MBR-partitioned disks through the Compatibility Support Module (CSM) that provides legacy BIOS compatibility. In that case, booting Linux on UEFI systems is the same as on legacy BIOS-based systems.

Microsoft Windows
The 64-bit versions of Windows Vista SP1 and later and 64-bit versions of Windows 8, 8.1, 10, and 11 can boot from a GPT disk that is larger than 2 TB.

Services
EFI defines two types of services: boot services and runtime services. Boot services are available only while the firmware owns the platform (i.e., before the  call), and they include text and graphical consoles on various devices, and bus, block and file services. Runtime services are still accessible while the operating system is running; they include services such as date, time and NVRAM access.

 * Graphics Output Protocol (GOP) services
 * The Graphics Output Protocol (GOP) provides runtime services; see also Graphics features section below. The operating system is permitted to directly write to the framebuffer provided by GOP during runtime mode.

 * UEFI Memory map services

 * SMM services

 * ACPI services

 * SMBIOS services

 * Devicetree services (for RISC processors)

 * Variable services
 * UEFI variables provide a way to store data, in particular non-volatile data. Some UEFI variables are shared between platform firmware and operating systems. Variable namespaces are identified by GUIDs, and variables are key/value pairs. For example, UEFI variables can be used to keep crash messages in NVRAM after a crash for the operating system to retrieve after a reboot.

 * Time services
 * UEFI provides time services. Time services include support for time zone and daylight saving fields, which allow the hardware real-time clock to be set to local time or UTC. On machines using a PC-AT real-time clock, by default the hardware clock still has to be set to local time for compatibility with BIOS-based Windows, unless using recent versions and an entry in the Windows registry is set to indicate the use of UTC.

Applications

Beyond loading an OS, UEFI can run UEFI applications, which reside as files on the EFI system partition. They can be executed from the UEFI Shell, by the firmware's boot manager, or by other UEFI applications. UEFI applications can be developed and installed independently of the original equipment manufacturers (OEMs).

A type of UEFI application is an OS boot loader such as GRUB, rEFInd, Gummiboot, and Windows Boot Manager, which loads some OS files into memory and executes them. Also, an OS boot loader can provide a user interface to allow the selection of another UEFI application to run. Utilities like the UEFI Shell are also UEFI applications.

Protocols
EFI defines protocols as a set of software interfaces used for communication between two binary modules. All EFI drivers must provide services to others via protocols. The EFI Protocols are similar to the BIOS interrupt calls.

Device drivers
In addition to standard instruction set architecture-specific device drivers, EFI provides for a ISA-independent device driver stored in non-volatile memory as EFI byte code or EBC. System firmware has an interpreter for EBC images. In that sense, EBC is analogous to Open Firmware, the ISA-independent firmware used in PowerPC-based Apple Macintosh and Sun Microsystems SPARC computers, among others.

Some architecture-specific (non-EFI Byte Code) EFI drivers for some device types can have interfaces for use by the OS. This allows the OS to rely on EFI for drivers to perform basic graphics and network functions before, and if, operating-system-specific drivers are loaded.

In other cases, the EFI driver can be filesystem drivers that allow for booting from other types of disk volumes. Examples include efifs for 37 file systems (based on GRUB2 code), used by Rufus for chain-loading NTFS ESPs.

Graphics features
The EFI 1.0 specification defined a UGA (Universal Graphic Adapter) protocol as a way to support graphics features. UEFI did not include UGA and replaced it with GOP (Graphics Output Protocol).

UEFI 2.1 defined a "Human Interface Infrastructure" (HII) to manage user input, localized strings, fonts, and forms (in the HTML sense). These enable original equipment manufacturers (OEMs) or independent BIOS vendors (IBVs) to design graphical interfaces for pre-boot configuration. UEFI uses UTF-16 to encode strings by default.

Most early UEFI firmware implementations were console-based. Today many UEFI firmware implementations are GUI-based.

EFI system partition
An EFI system partition, often abbreviated to ESP, is a data storage device partition that is used in computers adhering to the UEFI specification. Accessed by the UEFI firmware when a computer is powered up, it stores UEFI applications and the files these applications need to run, including operating system boot loaders. Supported partition table schemes include MBR and GPT, as well as El Torito volumes on optical discs. For use on ESPs, UEFI defines a specific version of the FAT file system, which is maintained as part of the UEFI specification and independently from the original FAT specification, encompassing the FAT32, FAT16 and FAT12 file systems. The ESP also provides space for a boot sector as part of the backward BIOS compatibility.

UEFI booting
Unlike the legacy PC BIOS, UEFI does not rely on boot sectors, defining instead a boot manager as part of the UEFI specification. When a computer is powered on, the boot manager checks the boot configuration and, based on its settings, then executes the specified OS boot loader or operating system kernel (usually boot loader ). The boot configuration is defined by variables stored in NVRAM, including variables that indicate the file system paths to OS loaders or OS kernels.

OS boot loaders can be automatically detected by UEFI, which enables easy booting from removable devices such as USB flash drives. This automated detection relies on standardized file paths to the OS boot loader, with the path varying depending on the computer architecture. The format of the file path is defined as \EFI\BOOT\BOOT.EFI; for example, the file path to the OS loader on an x86-64 system is \efi\boot\bootx64.efi, and \efi\boot\bootaa64.efi on ARM64 architecture. Booting UEFI systems from GPT-partitioned disks is commonly called UEFI-GPT booting. Despite the fact that the UEFI specification requires MBR partition tables to be fully supported, some UEFI firmware implementations immediately switch to the BIOS-based CSM booting depending on the type of boot disk's partition table, effectively preventing UEFI booting to be performed from EFI System Partition on MBR-partitioned disks. Such a boot scheme is commonly called UEFI-MBR.

It is also common for a boot manager to have a textual user interface so the user can select the desired OS (or setup utility) from a list of available boot options.

CSM booting
To ensure backward compatibility, UEFI firmware implementations on PC-class machines could support booting in legacy BIOS mode from MBR-partitioned disks through the Compatibility Support Module (CSM) that provides legacy BIOS compatibility. In this scenario, booting is performed in the same way as on legacy BIOS-based systems, by ignoring the partition table and relying on the content of a boot sector.

BIOS-style booting from MBR-partitioned disks is commonly called BIOS-MBR, regardless of it being performed on UEFI or legacy BIOS-based systems. Furthermore, booting legacy BIOS-based systems from GPT disks is also possible, and such a boot scheme is commonly called BIOS-GPT.

The Compatibility Support Module allows legacy operating systems and some legacy option ROMs that do not support UEFI to still be used. It also provides required legacy System Management Mode (SMM) functionality, called CompatibilitySmm, as an addition to features provided by the UEFI SMM. An example of such a legacy SMM functionality is providing USB legacy support for keyboard and mouse, by emulating their classic PS/2 counterparts.

In November 2017, Intel announced that it planned to phase out support CSM for client platforms by 2020.

In July, of 2022, Kaspersky Labs published information regarding a Rootkit designed to chain boot malicious code on machines using Intel's H81 chipset and the Compatibility Support module of affected motherboards.

In August 2023, Intel announced that it planned to phase out support CSM for server platforms by 2024.

As of today, all computers based on Intel platforms no longer have CSM support.

Network booting
The UEFI specification includes support for booting over network via the Preboot eXecution Environment (PXE). PXE booting network protocols include Internet Protocol (IPv4 and IPv6), User Datagram Protocol (UDP), Dynamic Host Configuration Protocol (DHCP), Trivial File Transfer Protocol (TFTP) and iSCSI.

OS images can be remotely stored on storage area networks (SANs), with Internet Small Computer System Interface (iSCSI) and Fibre Channel over Ethernet (FCoE) as supported protocols for accessing the SANs.

Version 2.5 of the UEFI specification adds support for accessing boot images over the HTTP.

Secure Boot
The UEFI specification defines a protocol known as Secure Boot, which can secure the boot process by preventing the loading of UEFI drivers or OS boot loaders that are not signed with an acceptable digital signature. The mechanical details of how precisely these drivers are to be signed are not specified. When Secure Boot is enabled, it is initially placed in "setup" mode, which allows a public key known as the "platform key" (PK) to be written to the firmware. Once the key is written, Secure Boot enters "User" mode, where only UEFI drivers and OS boot loaders signed with the platform key can be loaded by the firmware. Additional "key exchange keys" (KEK) can be added to a database stored in memory to allow other certificates to be used, but they must still have a connection to the private portion of the platform key. Secure Boot can also be placed in "Custom" mode, where additional public keys can be added to the system that do not match the private key.

Secure Boot is supported by Windows 8 and 8.1, Windows Server 2012 and 2012 R2, Windows 10, Windows Server 2016, 2019, and 2022, and Windows 11, VMware vSphere 6.5 and a number of Linux distributions including Fedora (since version 18), openSUSE (since version 12.3), RHEL (since version 7), CentOS (since version 7 ), Debian (since version 10), Ubuntu (since version 12.04.2), Linux Mint (since version 21.3)., and AlmaLinux OS (since version 8.4 ). , FreeBSD support is in a planning stage.

UEFI shell
UEFI provides a shell environment, which can be used to execute other UEFI applications, including UEFI boot loaders. Apart from that, commands available in the UEFI shell can be used for obtaining various other information about the system or the firmware, including getting the memory map, modifying boot manager variables , running partitioning programs , loading UEFI drivers, and editing text files.

Source code for a UEFI shell can be downloaded from the Intel's TianoCore UDK/EDK2 project. A pre-built ShellBinPkg is also available. Shell v2 works best in UEFI 2.3+ systems and is recommended over Shell v1 in those systems. Shell v1 should work in all UEFI systems.

Methods used for launching UEFI shell depend on the manufacturer and model of the system motherboard. Some of them already provide a direct option in firmware setup for launching, e.g. compiled x86-64 version of the shell needs to be made available as. Some other systems have an already embedded UEFI shell which can be launched by appropriate key press combinations. For other systems, the solution is either creating an appropriate USB flash drive or adding manually a boot option associated with the compiled version of shell.

Commands
The following is a list of commands supported by the EFI shell.

 * alias
 * attrib
 * bcfg
 * cd
 * cls
 * comp
 * cp
 * date
 * dblk
 * dh
 * dmpstore
 * echo
 * Edd30
 * EddDebug
 * edit
 * err
 * guid
 * help
 * load
 * ls
 * map
 * mem
 * memmap
 * mkdir
 * mm
 * mode
 * mount
 * pause
 * pci
 * reset
 * rm
 * set
 * stall
 * time
 * type
 * unload
 * ver
 * vol

Extensions
Extensions to UEFI can be loaded from virtually any non-volatile storage device attached to the computer. For example, an original equipment manufacturer (OEM) can distribute systems with an EFI system partition on the hard drive, which would add additional functions to the standard UEFI firmware stored on the motherboard's ROM.

UEFI Capsule
UEFI Capsule defines a Firmware-to-OS firmware update interface, marketed as modern and secure. Windows 8, Windows 8.1, Windows 10, and Fwupd for Linux each support the UEFI Capsule.

Hardware
Like BIOS, UEFI initializes and tests system hardware components (e.g. Memory training, PCIe link training, USB link training), and then loads the boot loader from a mass storage device or through a network connection. In x86 systems, the UEFI firmware is usually stored in the NOR flash chip of the motherboard.

Classes
UEFI machines can have one of the following classes, which were used to help ease the transition to UEFI:

 * Class 0: Legacy BIOS
 * Class 1: UEFI with a CSM interface and no external UEFI interface. The only UEFI interfaces are internal to the firmware.
 * Class 2: UEFI with CSM and external UEFI interfaces, eg. UEFI Boot.
 * Class 3: UEFI without a CSM interface and with an external UEFI interface.
 * Class 3+: UEFI class 3 that has Secure Boot enabled.

Starting from the 10th Gen Intel Core, Intel no longer provides Legacy Video BIOS for the iGPU (Intel Graphics Technology). Legacy boot with those CPUs requires a Legacy Video BIOS, which can still be provided by a video card.

SEC – Security Phase
This is the first stage of the UEFI boot but may have platform specific binary code that precedes it. (e.g., Intel ME, AMD PSP, CPU microcode). It consists of minimal code written in assembly language for the specific architecture. It initializes a temporary memory (often CPU cache as RAM, or SoC on-chip SRAM, CAR) and serves as the system's software root of trust with the option of verifying PEI before hand-off.

PEI – Pre-EFI Initialization
The second stage of UEFI boot consists of a dependency-aware dispatcher that loads and runs PEI modules (PEIMs) to handle early hardware initialization tasks such as main memory initialization (initialize memory controller and DRAM) and firmware recovery operations. Additionally, it is responsible for discovery of the current boot mode and handling many ACPI S3 operations. In the case of ACPI S3 resume, it is responsible for restoring many hardware registers to a pre-sleep state. PEI also uses CAR.

DXE – Driver Execution Environment
This stage consist of C modules and a dependency-aware dispatcher. With main memory now available, CPU, chipset, mainboard and other I/O devices are initialized in DXE and BDS.

BDS – Boot Device Select
BDS is a part of the DXE. In this stage, boot devices are initialized, UEFI drivers or Option ROMs of PCI devices are executed according to system configuration, and boot options are processed.

TSL – Transient System Load
This is the stage between boot device selection and hand-off to the OS. At this point one may enter UEFI shell, or execute an UEFI application such as the OS boot loader.

RT – Runtime
The UEFI hands off to the operating system (OS) after ExitBootServices is executed. A UEFI compatible OS is now responsible for exiting boot services triggering the firmware to unload all no longer needed code and data, leaving only runtime services code/data, e.g. SMM and ACPI. A typical modern OS will prefer to use its own programs (such as kernel drivers) to control hardware devices.

When a legacy OS is used, CSM will handle this call ensuring the system is compatible with legacy BIOS expectations.

Implementations
Intel's implementation of EFI is the Intel Platform Innovation Framework, codenamed Tiano. Tiano runs on Intel's XScale, Itanium, IA-32 and x86-64 processors, and is proprietary software, although a portion of the code has been released under the BSD license or Eclipse Public License (EPL) as TianoCore EDK II. TianoCore can be used as a payload for coreboot.

Phoenix Technologies' implementation of UEFI is branded as SecureCore Technology (SCT). American Megatrends offers its own UEFI firmware implementation known as Aptio, while Insyde Software offers InsydeH2O, and Byosoft offers ByoCore.

In December 2018, Microsoft released an open source version of its TianoCore EDK2-based UEFI implementation from the Surface line, Project Mu.

An implementation of the UEFI API was introduced into the Universal Boot Loader (Das U-Boot) in 2017. On the ARMv8 architecture Linux distributions use the U-Boot UEFI implementation in conjunction with GNU GRUB for booting (e.g. SUSE Linux ), the same holds true for OpenBSD. For booting from iSCSI iPXE can be used as a UEFI application loaded by U-Boot.

Platforms
Intel's first Itanium workstations and servers, released in 2000, implemented EFI 1.02.

Hewlett-Packard's first Itanium 2 systems, released in 2002, implemented EFI 1.10; they were able to boot Windows, Linux, FreeBSD and HP-UX; OpenVMS added UEFI capability in June 2003.

In January 2006, Apple Inc. shipped its first Intel-based Macintosh computers. These systems used EFI instead of Open Firmware, which had been used on its previous PowerPC-based systems. On 5 April 2006, Apple first released Boot Camp, which produces a Windows drivers disk and a non-destructive partitioning tool to allow the installation of Windows XP or Vista without requiring a reinstallation of Mac OS X (now macOS). A firmware update was also released that added BIOS compatibility to its EFI implementation. Subsequent Macintosh models shipped with the newer firmware.

During 2005, more than one million Intel systems shipped with Intel's implementation of UEFI. New mobile, desktop and server products, using Intel's implementation of UEFI, started shipping in 2006. For instance, boards that use the Intel 945 chipset series use Intel's UEFI firmware implementation.

Since 2005, EFI has also been implemented on non-PC architectures, such as embedded systems based on XScale cores.

The EDK (EFI Developer Kit) includes an NT32 target, which allows EFI firmware and EFI applications to run within a Windows application. But no direct hardware access is allowed by EDK NT32. This means only a subset of EFI application and drivers can be executed by the EDK NT32 target.

In 2008, more x86-64 systems adopted UEFI. While many of these systems still allow booting only the BIOS-based OSes via the Compatibility Support Module (CSM) (thus not appearing to the user to be UEFI-based), other systems started to allow booting UEFI-based OSes. For example, IBM x3450 server, MSI motherboards with ClickBIOS, HP EliteBook Notebook PCs.

In 2009, IBM shipped System x machines (x3550 M2, x3650 M2, iDataPlex dx360 M2) and BladeCenter HS22 with UEFI capability. Dell shipped PowerEdge T610, R610, R710, M610 and M710 servers with UEFI capability. More commercially available systems are mentioned in a UEFI whitepaper.

In 2011, major vendors (such as ASRock, Asus, Gigabyte, and MSI) launched several consumer-oriented motherboards using the Intel 6-series LGA 1155 chipset and AMD 9 Series AM3+ chipsets with UEFI.

With the release of Windows 8 in October 2012, Microsoft's certification requirements now require that computers include firmware that implements the UEFI specification. Furthermore, if the computer supports the "Connected Standby" feature of Windows 8 (which allows devices to have power management comparable to smartphones, with an almost instantaneous return from standby mode), then the firmware is not permitted to contain a Compatibility Support Module (CSM). As such, systems that support Connected Standby are incapable of booting Legacy BIOS operating systems.

In October 2017, Intel announced that it would remove legacy PC BIOS support from all its products by 2020, in favor of UEFI Class 3. By 2019, all computers based on Intel platforms no longer have legacy PC BIOS support.

Operating systems
An operating system that can be booted from a (U)EFI is called a (U)EFI-aware operating system, defined by (U)EFI specification. Here the term booted from a (U)EFI means directly booting the system using a (U)EFI operating system loader stored on any storage device. The default location for the operating system loader is, where short name of the machine type can be  ,  ,  ,   or. Some operating systems vendors may have their own boot loaders. They may also change the default boot location.

 * The Linux kernel has been able to use EFI at boot time since early 2000s, using the elilo EFI boot loader or, more recently, EFI versions of GRUB. Grub+Linux also supports booting from a GUID partition table without UEFI. The distribution Ubuntu added support for UEFI Secure Boot as of version 12.10. Furthermore, the Linux kernel can be compiled with the option to run as an EFI bootloader on its own through the EFI bootstub feature.
 * HP-UX has used (U)EFI as its boot mechanism on IA-64 systems since 2002.
 * OpenVMS has used EFI on IA-64 since its initial evaluation release in December 2003, and for production releases since January 2005. OpenVMS on x86-64 also uses UEFI to boot the operating system.
 * Apple uses EFI for its line of Intel-based Macs. Mac OS X v10.4 Tiger and Mac OS X v10.5 Leopard implement EFI v1.10 in 32-bit mode even on newer 64-bit CPUs, but full support arrived with OS X v10.8 Mountain Lion.
 * The Itanium versions of Windows 2000 (Advanced Server Limited Edition and Datacenter Server Limited Edition; based on the pre-release Windows Server 2003 codebase) implemented EFI 1.10 in 2002. Windows XP 64-bit Edition, Windows 2000 Advanced Server Limited Edition (pre-release Windows Server 2003) and Windows Server 2003 for IA-64, all of which are for the Intel Itanium family of processors, implement EFI, a requirement of the platform through the DIG64 specification.
 * Microsoft introduced UEFI for x64 Windows operating systems with Windows Vista SP1 and Windows Server 2008 however only UGA (Universal Graphic Adapter) 1.1 or Legacy BIOS INT 10h is supported; Graphics Output Protocol (GOP) is not supported. Therefore, PCs running 64-bit versions of Windows Vista SP1, Windows Vista SP2, Windows 7, Windows Server 2008 and Windows Server 2008 R2 are compatible with UEFI Class 2. 32-bit UEFI was originally not supported since vendors did not have any interest in producing native 32-bit UEFI firmware because of the mainstream status of 64-bit computing. Windows 8 finally introduced further optimizations for UEFI systems, including Graphics Output Protocol (GOP) support, a faster startup, 32-bit UEFI support, and Secure Boot support. Microsoft began requiring UEFI to run Windows with Windows 11, with IoT Enterprise editions of Windows 11 since version 24H2 exempt from the requirement.
 * On 5 March 2013, the FreeBSD Foundation awarded a grant to a developer seeking to add UEFI support to the FreeBSD kernel and bootloader. The changes were initially stored in a discrete branch of the FreeBSD source code, but were merged into the mainline source on 4 April 2014 (revision 264095); the changes include support in the installer as well. UEFI boot support for amd64 first appeared in FreeBSD 10.1 and for arm64 in FreeBSD 11.0.
 * Oracle Solaris 11.1 and later support UEFI boot for x86 systems with UEFI firmware version 2.1 or later. GRUB 2 is used as the boot loader on x86.
 * OpenBSD 5.9 introduced UEFI boot support for 64-bit x86 systems using its own custom loader, OpenBSD 6.0 extended that support to include ARMv7.
 * ArcaOS supports UEFI booting since the 5.1 release. ArcaOS' UEFI support emulates specific BIOS functionality which the operating system depends on (particularly interrupts INT 10H and INT 13H).

With virtualization

 * HP Integrity Virtual Machines provides UEFI boot on HP Integrity Servers. It also provides a virtualized UEFI environment for the guest UEFI-aware OSes.
 * Intel hosts an Open Virtual Machine Firmware project on SourceForge.
 * VMware Fusion 3 software for Mac OS X can boot Mac OS X Server virtual machines using UEFI.
 * VMware Workstation prior to version 11 unofficially supports UEFI, but is manually enabled by editing the .vmx file. VMware Workstation version 11 and above supports UEFI, independently of whether the physical host system is UEFI-based. VMware Workstation 14 (and accordingly, Fusion 10) adds support for the Secure Boot feature of UEFI.
 * The VMware ESXi 5.0 hypervisor officially supports UEFI. Version 6.5 adds support for Secure Boot.
 * VirtualBox has implemented UEFI since 3.1, but is limited to Unix/Linux operating systems and Windows 8 and later (does not work with Windows Vista x64 and Windows 7 x64).
 * QEMU/KVM can be used with the Open Virtual Machine Firmware (OVMF) provided by TianoCore.
 * The second generation of the Microsoft Hyper-V virtual machine supports virtualized UEFI.
 * Google Cloud Platform Shielded VMs support virtualized UEFI to enable Secure Boot.

Applications development
EDK2 Application Development Kit (EADK) makes it possible to use standard C library functions in UEFI applications. EADK can be freely downloaded from the Intel's TianoCore UDK / EDK2 SourceForge project. As an example, a port of the Python interpreter is made available as a UEFI application by using the EADK. The development has moved to GitHub since UDK2015.

A minimalistic "hello, world" C program written using EADK looks similar to its usual C counterpart:

Criticism
Numerous digital rights activists have protested UEFI. Ronald G. Minnich, a co-author of coreboot, and Cory Doctorow, a digital rights activist, have criticized UEFI as an attempt to remove the ability of the user to truly control the computer. It does not solve the BIOS's long-standing problems of requiring two different drivers—one for the firmware and one for the operating system—for most hardware.

Open-source project TianoCore also provides UEFIs. TianoCore lacks the specialized drivers that initialize chipset functions, which are instead provided by coreboot, of which TianoCore is one of many payload options. The development of coreboot requires cooperation from chipset manufacturers to provide the specifications needed to develop initialization drivers.

Secure Boot
In 2011, Microsoft announced that computers certified to run its Windows 8 operating system had to ship with Microsoft's public key enrolled and Secure Boot enabled. Following the announcement, the company was accused by critics and free software/open source advocates (including the Free Software Foundation) of trying to use the Secure Boot functionality of UEFI to hinder or outright prevent the installation of alternative operating systems such as Linux. Microsoft denied that the Secure Boot requirement was intended to serve as a form of lock-in, and clarified its requirements by stating that x86-based systems certified for Windows 8 must allow Secure Boot to enter custom mode or be disabled, but not on systems using the ARM architecture. Windows 10 allows OEMs to decide whether or not Secure Boot can be managed by users of their x86 systems.

Other developers raised concerns about the legal and practical issues of implementing support for Secure Boot on Linux systems in general. Former Red Hat developer Matthew Garrett noted that conditions in the GNU General Public License version 3 may prevent the use of the GNU GRand Unified Bootloader without a distribution's developer disclosing the private key (however, the Free Software Foundation has since clarified its position, assuring that the responsibility to make keys available was held by the hardware manufacturer), and that it would also be difficult for advanced users to build custom kernels that could function with Secure Boot enabled without self-signing them. Other developers suggested that signed builds of Linux with another key could be provided, but noted that it would be difficult to persuade OEMs to ship their computers with the required key alongside the Microsoft key.

Several major Linux distributions have developed different implementations for Secure Boot. Garrett himself developed a minimal bootloader known as a shim, which is a precompiled, signed bootloader that allows the user to individually trust keys provided by Linux distributions. Ubuntu 12.10 uses an older version of shim pre-configured for use with Canonical's own key that verifies only the bootloader and allows unsigned kernels to be loaded; developers believed that the practice of signing only the bootloader is more feasible, since a trusted kernel is effective at securing only the user space, and not the pre-boot state for which Secure Boot is designed to add protection. That also allows users to build their own kernels and use custom kernel modules as well, without the need to reconfigure the system. Canonical also maintains its own private key to sign installations of Ubuntu pre-loaded on certified OEM computers that run the operating system, and also plans to enforce a Secure Boot requirement as wellrequiring both a Canonical key and a Microsoft key (for compatibility reasons) to be included in their firmware. Fedora also uses shim, but requires that both the kernel and its modules be signed as well.

It has been disputed whether the operating system kernel and its modules must be signed as well; while the UEFI specifications do not require it, Microsoft has asserted that their contractual requirements do, and that it reserves the right to revoke any certificates used to sign code that can be used to compromise the security of the system. In Windows, if Secure Boot is enabled, all kernel drivers must be digitally signed; non-WHQL drivers may be refused to load. In February 2013, another Red Hat developer attempted to submit a patch to the Linux kernel that would allow it to parse Microsoft's authenticode signing using a master X.509 key embedded in PE files signed by Microsoft. However, the proposal was criticized by Linux creator Linus Torvalds, who attacked Red Hat for supporting Microsoft's control over the Secure Boot infrastructure.

On 26 March 2013, the Spanish free software development group Hispalinux filed a formal complaint with the European Commission, contending that Microsoft's Secure Boot requirements on OEM systems were "obstructive" and anti-competitive.

At the Black Hat conference in August 2013, a group of security researchers presented a series of exploits in specific vendor implementations of UEFI that could be used to exploit Secure Boot.

In August 2016 it was reported that two security researchers had found the "golden key" security key Microsoft uses in signing operating systems. Technically, no key was exposed, however, an exploitable binary signed by the key was. This allows any software to run as though it was genuinely signed by Microsoft and exposes the possibility of rootkit and bootkit attacks. This also makes patching the fault impossible, since any patch can be replaced (downgraded) by the (signed) exploitable binary. Microsoft responded in a statement that the vulnerability only exists in ARM architecture and Windows RT devices, and has released two patches; however, the patches do not (and cannot) remove the vulnerability, which would require key replacements in end user firmware to fix.

On March 1, 2023, researchers from ESET Cybersecurity Firm reported “The first in-the-wild UEFI bootkit bypassing UEFI Secure Boot” named ‘BlackLotus’ in their public analyses findings describing the theory behind its mechanics exploiting the patches that “do not (and cannot) remove the vulnerability”.

Many Linux distributions support UEFI Secure Boot now, such as RHEL (RHEL 7 and later), CentOS (CentOS 7 and later ), Ubuntu, Fedora, Debian (Debian 10 and later ), OpenSUSE, SUSE Linux.

Firmware problems
The increased prominence of UEFI firmware in devices has also led to a number of technical problems blamed on their respective implementations.

Following the release of Windows 8 in late 2012, it was discovered that certain Lenovo computer models with Secure Boot had firmware that was hardcoded to allow only executables named "Windows Boot Manager" or "Red Hat Enterprise Linux" to load, regardless of any other setting. Other problems were encountered by several Toshiba laptop models with Secure Boot that were missing certain certificates required for its proper operation.

In January 2013, a bug surrounding the UEFI implementation on some Samsung laptops was publicized, which caused them to be bricked after installing a Linux distribution in UEFI mode. While potential conflicts with a kernel module designed to access system features on Samsung laptops were initially blamed (also prompting kernel maintainers to disable the module on UEFI systems as a safety measure), Matthew Garrett discovered that the bug was actually triggered by storing too many UEFI variables to memory, and that the bug could also be triggered under Windows under certain conditions. In conclusion, he determined that the offending kernel module had caused kernel message dumps to be written to the firmware, thus triggering the bug.

title: UEFI


text:
HMS Surprise (replica ship)

HMS Surprise is a modern tall ship built at Lunenburg, Nova Scotia, Canada. The vessel was built in 1970 as HMS Rose to a Phil Bolger design based on the original 18th-century British Admiralty drawings of HMS Rose (1757), a 20-gun sixth-rate post ship from 1757.

As HMS Rose
The ship was meant to be a close replica of the original Rose, but still fill a commercial function. John Fitzhugh Millar commissioned the ship's construction in anticipation of the US Bicentennial in 1976. In conjunction with this project, he appeared on the television show To Tell the Truth in 1974 and stumped the panel. Millar gave Bolger copies of the original British Admiralty drawings. Bolger modified the hull shape below the water line, sharpening up her entry so she sailed to windward better. Unlike some square-riggers, she could sail two points (22-1/2 degrees) on the wind provided that seas remained under four feet or so. Bolger also changed the arrangement of her decks, at the bank's insistence, so that she could be used as a tavern and restaurant, though she was never used as such.

Rose was built at the Smith and Rhuland shipyard in Lunenburg, a yard which had established a reputation for large and successful replicas such as HMS Bounty in 1960 and  Bluenose II in 1963.

The ship was inspected and certified by the United States Coast Guard. She spent the first ten years of her life in Newport, Rhode Island sailing in Newport Harbor and as a dockside attraction.

In the summer of 1972, Rose was hired for the film The Man Without a Country, a made-for-television production. Norman Rosemont Productions couldn't find the money to take the ship out sailing, so all the filming was shot with sails set, as the ship was securely moored to the pier, next to the causeway to Goat Island. During filming Cliff Robertson had to hide that he had a broken leg at the time.

In 1984, already in serious disrepair, she was purchased by Kaye Williams and brought to Bridgeport, Connecticut, and operated as a sail training vessel in the 1980s and 1990s, run by the HMS Rose Foundation based in Bridgeport, Connecticut, United States. In her lifetime as Rose, her figurehead had to be replaced twice, each time slightly upgraded. One was damaged in a storm off Bermuda on her way to Norfolk, Virginia, in June 1998. The figurehead was named in fun as "Chester" by the crew.

Transformation into HMS Surprise
The ship was sold to the 20th Century Fox film studio in March 2001, and underwent extensive modifications to be used in the making of the film Master and Commander: The Far Side of the World, in which she portrayed the Royal Navy frigate HMS HMS Surprise (1796) with a story based on several of the books by Patrick O'Brian. The modifications included a reshaped stern, all deck structures removed, the single ship's wheel replaced by a double wheel, period fighting tops fitted, new sails, and the figurehead replaced.

Renaming as HMS Surprise
After the film was complete, the ship was leased and then purchased by the Maritime Museum of San Diego which has restored her to sailing condition as of September 2007. The ship has officially been re-registered as "HMS Surprise" in honor of her role in the film. She sails several times a year, often with the museum's other tall ships, the schooner Californian and the 1863 barque  Star of India. In 2010, she portrayed HMS Providence in the Disney adventure film Pirates of the Caribbean: On Stranger Tides.

Related facts
Although she is known by the prefix HMS, meaning His (or Her) Majesty's Ship, she has never been commissioned in the Royal Navy.

In 1991, the Connecticut General Assembly passed "An Act Concerning the HMS Rose" in which the ship was commissioned as a vessel of the Connecticut Naval Militia. The act stated that the H.M.S. Rose Foundation was responsible for maintaining the ship, but when the ship was sold to 20th Century Fox, the statute was not repealed and is still in effect.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: HMS Surprise (replica ship)


text:
Andrei Sinyavsky

Andrei Donatovich Sinyavsky (Андре́й Дона́тович Синя́вский; 8 October 1925 – 25 February 1997) was a Russian writer and Soviet dissident known as a defendant in the Sinyavsky–Daniel trial of 1965.

Sinyavsky was a literary critic for Novy Mir and wrote works critical of Soviet society under the pseudonym Abram Tertz (Абрам Терц) published in the West to avoid censorship in the Soviet Union. Sinyavsky and Yuli Daniel were convicted of Anti-Soviet agitation in a show trial, becoming the first Soviet writers convicted solely for their works and for fiction, and served six years at a Gulag camp. Sinyavsky emigrated to France in 1973 where he became a professor of Russian literature and published numerous autobiographical and retrospective works.

Early life and education
Andrei Donatovich Sinyavsky was born on 8 October 1925 in Moscow, Russia, the son of Donat Evgenievich Sinyavsky, a Russian nobleman from Syzran who became a member of the Left Socialist-Revolutionaries, and a mother of a Russian peasant background. Donat was arrested several times by the Bolsheviks after the October Revolution as an "enemy of the people", and during his last stay in jail the medical authorities took his electroencephalographic reading. Sinyavsky described his father's experiences in the autobiographical novel Goodnight!

Sinyavsky's family was evacuated to Syzran following the German invasion of the Soviet Union in 1941, where he graduated from school in 1943. Sinyavsky was drafted into the Red Army after graduation and served as a radio engineer at an airfield. In 1945, Sinyavsky became a philology student at Moscow State University, becoming a full-time student following his demobilization from the Red Army the next year, and studied the works of Vladimir Mayakovsky. Sinyavsky graduated in 1949 and attended graduate school where he successfully defended his thesis in 1952. Sinyavsky worked at the Gorky Institute of World Literature in Moscow and taught at Moscow State University's Faculty of Journalism and the Moscow Art Theatre School. By the end of 1960, he was admitted into the Union of Soviet Writers.

Sinyavsky became one of the leading literary critics of the Novy Mir magazine, at the time headed by Aleksandr Tvardovsky. In the early 1960s, Novy Mir was considered the most liberal legal publications in the Soviet Union, and Sinyavsky began leaning towards a dissident position. In November 1962, Novy Mir became famous for publishing Aleksandr Solzhenitsyn's groundbreaking One Day in the Life of Ivan Denisovich, a novella about a prisoner of the Gulag. Sinyavsky, a protégé of Boris Pasternak, described the realities of Soviet life in short fiction stories which were often critical in nature. Sinyavsky published his novels in the West under the pseudonym Abram Tertz, derived from the name of a historical Russian Jewish gangster, although Sinyavsky himself was not Jewish. Sinyavsky's works were naturally rejected for publication by the Communist Party of the Soviet Union (CPSU) during a time of extreme censorship.

Sinyavsky–Daniel trial
On 4 September 1965, Sinyavsky was arrested along with fellow-writer and friend Yuli Daniel, and tried in the first Soviet show trial during which writers were openly convicted solely for their literary work. Sinyavsky and Daniel were arrested as part of widespread political repression in the Soviet Union due to their works critical of Soviet life being published abroad. Legally, Sinyavsky and Daniel could not be charged for their publications outside the Soviet Union, and instead were charged under Article 70 of the Russian SFSR Criminal Code for producing materials labeled as "Anti-Soviet agitation". This was the first time anti-Soviet laws were applied to works of fiction. Dozens of Soviet writers and intellectuals came to the defence of Sinyavsky and Daniel, and on 5 December 1965 held the Glasnost meeting in Moscow, the first spontaneous public political demonstration in the Soviet Union after the Second World War. The Sinyavsky–Daniel trial was accompanied by harsh propaganda campaigns in the Soviet media, perceived as a sign of demise of the Khrushchev Thaw which had allowed greater freedoms of expression during the late 1950s and early 1960s.

On 14 February 1966, Sinyavsky was sentenced to seven years on charges of "anti-Soviet activity" for the opinions of his fictional characters. After the trial, 63 supporters of Sinyavsky and Daniel signed a petition requesting their release. In response to the petition, members of the Secretariat of the Union of Soviet Writers spoke out against Sinyavsky and Daniel. As historian Fred Coleman writes, "Historians now have no difficulty pinpointing the birth of the modern Soviet dissident movement. It began in February 1966 with the trial of Andrei Sinyavsky and Yuli Daniel, two Russian writers who ridiculed the Communist regime in satires smuggled abroad and published under pen names... Little did they realize at the time that they were starting a movement that would help end Communist rule."

Sinyavsky was forced to work as a stevedore at the Dubravlag, a labor camp (katorga) of the Gulag system located near Yavas, Mordovian ASSR. Sinyavsky was released early in 1971 as part of an initiative by Yuri Andropov, the Chairman of the KGB and the future General Secretary of the CPSU.

Later years and death
In 1973, Sinyavsky was allowed to emigrate to France at the invitation of Claude Frioux, a professor at the University of Paris 8 Vincennes-Saint-Denis specializing in Russia. Sinyavsky became a professor of Russian literature at Sorbonne University, co-founded the Russian-language almanac Sintaksis with his wife Maria Rozanova, and actively contributed to Radio Liberty. Sinyavsky and Rozanova's son, Iegor Gran, graduated from École Centrale Paris and became a novelist.

On 17 October 1991, Sinyavsky was featured in a report received by Izvestia on the review of convictions for several prominent Soviet individuals due to lack of corpus delicti in their actions. Sinyavsky, Yuli Daniel, Kārlis Ulmanis, Nikolay Timofeev-Ressovsky were considered for "rehabilitation" only two months before the dissolution of the Soviet Union.

In early 1996, Sinyavsky suffered a heart attack, and later that year was diagnosed with lung cancer with metastases in the brain. Sinyavsky underwent unsuccessful operations and radiotherapy at the Curie Institute. Sinyavsky died in 1997 in Fontenay-aux-Roses, near Paris, and was buried there by the Russian Orthodox priest and writer Vladimir Vigilyansky with Andrei Voznesensky in attendance.

Sinyavsky was the catalyst for the formation of the Russian-English translation team of Larissa Volokhonsky and Richard Pevear, who have translated a number of works by Mikhail Bulgakov, Anton Chekhov, Fyodor Dostoyevski, Nikolai Gogol, and Leo Tolstoy. Volokhonsky, who was born and raised in Leningrad (now St. Petersburg), first visited the United States in the early 1970s and happened across Pevear's Hudson Review article about Sinyavsky. At the time, Pevear believed Sinyavsky was still in a Russian prison; Volokhonsky had just helped him immigrate to Paris. Pevear was surprised and pleased to be mistaken: "Larissa had just helped Sinyavsky leave Russia," Pevear recalled. "And she let me know that, while I'd said he was still in prison, he was actually in Paris. I was glad to know it."

title: Andrei Sinyavsky


text:
EFI

EFI may refer to:

Given name

 * Efi Arazi (1937–2013), Israeli businessman and high-tech entrepreneur
 * Efi Foufoula-Georgiou (born 1957), Greek-American environmental engineer
 * Efi Oshaya (born 1956), Israeli politician
 * Efi Thodi (born 1934), Greek singer

Surname

 * Andrey Efi (born 1960), Russian artist
 * Tufuga Efi (born 1937), Samoan politician

Technology

 * Electronic fuel injection
 * Exploding foil initiator
 * Extensible Firmware Interface, a computer firmware standard
 * EFI system partition

Other uses

 * École Française d'Islamabad, a French international school in Pakistan
 * EFI Automotive, a French automotive company
 * Efik language
 * Electronics for Imaging, an American digital printing company
 * Enrico Fermi Institute, at the University of Chicago
 * Enterprise Florida, an American economic development organization
 * Environmentalist Foundation of India, a wildlife conservation group
 * Enzyme Function Initiative, a computational biology project
 * Equestrian Federation of India
 * Equestrian Federation of Ireland, now Horse Sport Ireland
 * European Federation for Immunogenetics, a scientific society
 * European Forest Institute, an international organisation
 * European Friends of Israel, a political organization
 * Evangelical Friends International, a Christian religious organization
 * Expeditionary Forces Institute, of the British Navy, Army and Air Force Institutes

title: EFI


text:
Visayan hornbill

The Visayan hornbill (Penelopides panini) is a hornbill found in rainforests of Western Visayas region which includes the islands of Panay, Negros,Cebu and Guimaras, as well as the island of Masbate, and formerly Ticao, in the Philippines. It formerly included all other Philippine tarictic hornbills as subspecies, in which case the common name of the 'combined species' was shortened to tarictic hornbill.

Taxonomy
The Visayan hornbill was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1780 in his Histoire Naturelle des Oiseaux. The bird was also illustrated in a hand-coloured plate engraved by François-Nicolas Martinet in the Planches Enluminées D'Histoire Naturelle which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text. Neither the plate caption nor Buffon's description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name Buceros panini in his catalogue of the Planches Enluminées. The type locality is the island of Panay in the Philippines. The Visayan hornbill is now placed in the genus Penelopides that was introduced in 1849 by the German naturalist Ludwig Reichenbach in a plate of the hornbills. The origin of the generic name is uncertain but it may be a combination of the Latin pene meaning "almost" or "nearly", the Ancient Greek lophos meaning "crest" and -oideēs "resembling". The specific epithet panini is a Latinized form of "Panay". The common English name refers to the Visayan Islands. These are located in the central part of the Philippines and include the island of Panay.

Two subspecies are recognized:
 * P. p. panini – (Boddaert, 1783) : Visayan tarictic hornbill, nominate, found on Panay, Negros, Masbate and Guimaras
 * P. p. ticaensis – Hachisuka, 1930 : Ticao tarictic hornbill, found on Ticao Island (likely extinct)

Description
The adults show sexual dimorphism. The male has a creamy-white head and neck, a white upper chest, a reddish-brown lower chest and uppertail-coverts, and a creamy-white buff tail with a broad black tip. The bill and casque are blackish; the former with yellowish ridges. The bare ocular skin is pinkish-white. The tail and bill of the female resemble that of the male, but otherwise the plumage of the female is black, and the ocular skin is blue.

Diet and behavior
Visayan hornbills live in groups and frequent the canopy of rainforests. These birds are noisy and emit an incessant sound that sounds like ta-rik-tik, hence the name. Despite their noise they are difficult to find, being well camouflaged by the dense foliage.

The principal food of Visayan hornbill is fruit. It also eats insects, beetles, ants and earthworms (rarely).

Conservation
This is a highly endangered species. The total population is estimated at 1800 individuals. There has been a heavy decline in population due to hunting and loss of habitat caused by deforestation. The subspecies ticaensis was described as "abundant" in 1905, but almost the entire forest on the island was replaced by plantations and settlements in the 20th century. The last time the Ticao tarictic was seen was in 1971, and it is now likely to be extinct. If confirmed, this is the first taxon of hornbill to go extinct in recorded history; many other taxa in the family are now at risk.

Captivity
This species has just been imported from Panay in the Philippines by Chester Zoo, England. There are two pairs at Chester, and two pairs at Avifauna in the Netherlands, amongst other collections.

In the past, the Los Angeles Zoo has bred this species, but it is not known whether these birds were pure Penelopides panini panini, so it may not be the first captive breeding of this species; that title may go to a breeding centre on Panay, where Chester's birds came from. The Chester zoo has bred this species.

title: Visayan hornbill


text:
Talk:Biosophy

Who regarded Zapffe as a nihilist? - Sigg3.net 21:05, 29 Jul 2004 (UTC)

External links modified
Hello fellow Wikipedians,

I have just added archive links to 1 one external link on Biosophy. Please take a moment to review my edit. You may add after the link to keep me from modifying it, if I keep adding bad data, but formatting bugs should be reported instead. Alternatively, you can add to keep me off the page altogether, but should be used as a last resort. I made the following changes:
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Cheers.—cyberbot II  Talk to my owner :Online 15:29, 29 March 2016 (UTC)

title: Talk:Biosophy


text:
Talk:Stoewer

Untitled
Dear Wikipedians, In this article I had to correct model names that were used in English translation. I think the original German names have to be used and translations should be added for explanation only. Otherwise, the same brand would have been used in different forms in different languages. E.g. Gryf is Greif in German, Grifo in Italian and Griff in Hungarian etc.

Regards, --Millisits 21:06, 29 Jul 2004 (UTC)

title: Talk:Stoewer


text:
Jacob Froese

Jacob M. Froese (November 28, 1917 – June 14, 2003) was a politician in the Canadian province of Manitoba. He was the province's only Social Credit MLA between 1959 and 1973, and was the party's leader for most if not all of the period from 1959 to 1977.

The son of Jacob J. Froese and Margaret Enns, Froese was born in Winkler, Manitoba to Jacob J. and Margaret (Enns) Froese. His Father was an Old Colony Mennonite Church bishop from 1936 to 1968. He was educated in the local school system and worked as a farmer, also becoming a leading figure in the Winkler Credit Union Society. He married Mary Peters in 1941, and together they had 10 children. Early in his life, he was a Young Liberal.

Froese was elected to the Manitoba legislature for the riding of Rhineland in a November 1959 by-election, defeating a Progressive Conservative candidate by 91 votes. He was re-elected by 33 votes in the 1962 general election, and by greater margins in elections of 1966 and 1969.

The Social Credit Party of Manitoba was largely moribund in this period, and it never came close to electing a second MLA during Froese's time in the legislature. A popular local figure, Froese was for all intents and purposes an independent parliamentarian.

Manitoba politics became increasingly polarized between the New Democratic Party and Progressive Conservative Party during the 1970s. Froese was defeated by Progressive Conservative candidate Arnold Brown in the 1973 election, and finished a poor fourth in a bid for re-election four years later. He ran as a federal Social Credit candidate in Lisgar in the 1974 Canadian election, but finished fourth in this race as well.

In the 1981 provincial election, Froese ran for provincial parliament as a member of the Progressive Party of Manitoba, founded by former NDP cabinet minister Sidney Green. He received only 349 votes, and did not attempt any further political comebacks.

Froese died at home in Winkler in 2003. His funeral was held at the Winkler Mennonite Brethren Church, of which he had long been a member.

title: Jacob Froese


text:
LAPB

Link Access Procedure, Balanced (LAPB) implements the data link layer as defined in the X.25 protocol suite. LAPB is a bit-oriented protocol derived from HDLC that ensures that frames are error free and in the correct sequence. LAPB is specified in ITU-T Recommendation X.25 and ISO/IEC 7776. It implements the connection-mode data link service in the OSI Reference Model as defined by ITU-T Recommendation X.222.

LAPB is used to manage communication and packet framing between data terminal equipment (DTE) and the data circuit-terminating equipment (DCE) devices in the X.25 protocol stack. LAPB is essentially HDLC in Asynchronous Balanced Mode (ABM). LAPB sessions can be established by either the DTE or DCE. The station initiating the call is determined to be the primary, and the responding station is the secondary.

Frame types

 * I-Frames (Information frames): Carries upper-layer information and some control information. I-frame functions include sequencing, flow control, and error detection and recovery. I-frames carry send and receive sequence numbers.
 * S-Frames (Supervisory Frames): Carries control information. S-frame functions include requesting and suspending transmissions, reporting on status, and acknowledging the receipt of I-frames. S-frames carry only receive sequence numbers.
 * U-Frames (Unnumbered Frames): carries control information. U-frame functions include link setup and disconnection, as well as error reporting. U-frames carry no sequence numbers

Frame format
Flag – The value of the flag is always 0x7E. In order to ensure that the bit pattern of the frame delimiter flag does not appear in the data field of the frame (and therefore cause frame misalignment), a technique known as Bit stuffing is used by both the transmitter and the receiver.

Address field – In LAPB, this field has no meaning since the protocol works in a point to point mode and the DTE network address is represented in the layer 3 packets. This byte is therefore put to a different use; it separates the link commands from the responses and can have only two values: 0x01 and 0x03. 01 identifies frames containing commands from DTE to DCE and responses to these commands from DCE to DTE. 03 is used for frames containing commands from DCE to DTE and for responses from DTE to DCE. Therefore, one side must be configured as a Layer 2 DTE and the other as a Layer 2 DCE (you must not confuse this with the more familiar Layer 1 DCE and DTE designations).

Control field – it serves to identify the type of the frame. In addition, it includes sequence numbers, control features and error tracking according to the frame type.

Modes of operation – LAPB works in the Asynchronous Balanced Mode (ABM). This mode is balanced (i.e., no master/slave relationship) and is signified by the SABM(E)/SM frame. Each station may initialize, supervise, recover from errors, and send frames at any time. The DTE and DCE are treated as equals.

FCS – The Frame Check Sequence enables a high level of physical error control by allowing the integrity of the transmitted frame data to be checked.

Window size – LAPB supports an extended window size (modulo 128 and modulo 32768) where the maximum number of outstanding frames for acknowledgment is raised from 7 (modulo 8) to 127 (modulo 128) and 32767 (modulo 32768).

Protocol operation
LAPB has no master/slave node relationships. The sender uses the Poll bit in command frames to insist on an immediate response. In the response frame this same bit becomes the receivers Final bit. The receiver always turns on the Final bit in its response to a command from the sender with the Poll bit set. The P/F bit is generally used when either end becomes unsure about proper frame sequencing because of a possible missing acknowledgment, and it is necessary to re-establish a point of reference. It is also used to trigger an acknowledgment of outstanding I-frames.

Node addressing
The following table shows which addresses are placed into the LAPB frame when issuing commands and responses from DTE to DCE and DCE to DTE using single link operation or multilink operation:

title: LAPB


text:
Data access object

In software, a data access object (DAO) is a pattern that provides an abstract interface to some type of database or other persistence mechanism. By mapping application calls to the persistence layer, the DAO provides data operations without exposing database details. This isolation supports the single responsibility principle. It separates the data access the application needs, in terms of domain-specific objects and data types (the DAO's public interface), from how these needs can be satisfied with a specific DBMS (the implementation of the DAO).

Although this design pattern is applicable to most programming languages, most software with persistence needs, and most databases, it is traditionally associated with Java EE applications and with relational databases (accessed via the JDBC API because of its origin in Sun Microsystems' best practice guidelines "Core J2EE Patterns".

This object can be found in the Data Access layer of the 3-Tier Architecture.

There are various ways in which this object can be implemented:
 * One DAO for each table.
 * One DAO for all the tables for a particular DBMS.
 * Where the SELECT query is limited only to its target table and cannot incorporate JOINS, UNIONS, subqueries and Common Table Expressions (CTEs)
 * Where the SELECT query can contain anything that the DBMS allows.

Advantages
Using data access objects (DAOs) offers a clear advantage: it separates two parts of an application that don't need to know about each other. This separation allows them to evolve independently. If business logic changes, it can rely on a consistent DAO interface. Meanwhile, modifications to persistence logic won't affect DAO clients.

All details of storage are hidden from the rest of the application (see information hiding). Unit testing code is facilitated by substituting a test double for the DAO in the test, thereby making the tests independent of the persistence layer.

In the context of the Java programming language, DAO can be implemented in various ways. This can range from a fairly simple interface that separates data access from the application logic, to frameworks and commercial products.

Technologies like Java Persistence API and Enterprise JavaBeans come built into application servers and can be used in applications that use a Java EE application server. Commercial products such as TopLink are available based on object–relational mapping (ORM). Popular open source ORM software includes Doctrine, Hibernate, iBATIS and JPA implementations such as Apache OpenJPA.

Disadvantages
Potential disadvantages of using DAO include leaky abstraction, code duplication, and abstraction inversion. In particular, the abstraction of the DAO as a regular Java object can obscure the high cost of each database access. Developers may inadvertently make multiple database queries to retrieve information that could be returned in a single operation. If an application requires multiple DAOs, the same create, read, update, and delete code may have to be written for each DAO.

Note that these disadvantages only appear when you have a separate DAO for each table and the SELECT query is prevented from accessing anything other than the target table.

Tools and frameworks

 * ODB compiler-based object–relational mapping (ORM) system for C++
 * ORMLite: Lightweight object–relational mapping (ORM) framework in Java for JDBC and Android
 * Microsoft Entity Framework
 * DBIx::Class object–relational mapping (ORM) module for Perl
 * TuxORM: Simple object–relational mapping (ORM) library in Java for JDBC
 * Persist (Java tool) Java-based object–relational mapping and data access object tool

title: Data access object


text:
Talk:Sook Ching

Untitled
Should "undersirables" actually be "undesirables"? The fact that the word is in quotes suggests that the spelling was deliberate, not a typo...--KBrown 21:11, 29 Jul 2004 (UTC)

I couldn't find any other reference to the "Chopsticks" civilian war memorial being built over a mass grave. Jan 29. 2005

 * Please refer to Blackburn's article, listed on "Further Reading" for more information on "Chopsticks."

 * ~Bourquie - 10 Jul 2004, 16:15 MDT

The "Death toll" section of this page seems a bit biased and is poorly worded.

need references
Occasionally I see sentences that look pretty biased and questionable, but there are no references to use for checking. For example, this sentence "Most of those identified were innocent people and were just killed brutally without reason." How do we know that is true? There are references listed at the bottom of the page, but no indications as to which references provide specific pieces of information. Readin (talk) 15:55, 15 June 2009 (UTC)

Requested move

 * The following discussion is an archived discussion of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the proposal was not moved per the discussion.--Fuhghettaboutit (talk) 11:54, 18 October 2012 (UTC)

Sook Ching massacre → Sook Ching – The term "massacre" is redundant and the current title is not as common in sources as the simpler proposed title. Srnec (talk) 16:55, 8 October 2012 (UTC)

Survey

 * Feel free to state your position on the renaming proposal by beginning a new line in this section with  or  , then sign your comment with  . Since polling is not a substitute for discussion, please explain your reasons, taking into account Wikipedia's policy on article titles.

 * Poorly-informed weak oppose - If only because some of the non-English Wikipedia articles are calling it that and Google autocompletes "Sook Ching massacre" in my locality. I'll reconsider my vote when I hear other's expert views as to the common name. Marcus Qwertyus (talk) 23:02, 8 October 2012 (UTC)

 * Weak favor - If, as you claim, the title is redundant and Sook Ching by itself is the usual term used in the literature, then go with it. I don't think the massacre is well enough known for the redundant title to be needed for reasons of familiarity, Google notwithstanding. --Yaush (talk) 17:57, 9 October 2012 (UTC)
 * Oppose the current title is helpful. It isn't well known enough (even if it should be) to stand on its own. Now if I searched "Singapore massacre" then this comes up 1st. The name "sook ching" isn't memorable to most people - it isn't pinyin so multiple spellings are possible. I'd just leave it be. In ictu oculi (talk) 10:47, 16 October 2012 (UTC)
 * Mild oppose. Agree with In ictu oculi: the 'massacre' in there provides a very handy hint about the article's content. Jpatokal (talk) 22:41, 16 October 2012 (UTC)

Discussion

 * Any additional comments:

 * The above discussion is preserved as an archive of the proposal. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

Requested move 06 February 2014

 * The following discussion is an archived discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section.

The result of the move request was: moved per request. Favonian (talk) 18:13, 15 February 2014 (UTC)

Sook Ching massacre → Sook Ching – The "massacre" is redundant, like "Holocaust Massacre". For evidence of usage, see below. Srnec (talk) 00:48, 6 February 2014 (UTC)

Survey

 * Feel free to state your position on the renaming proposal by beginning a new line in this section with  or  , then sign your comment with  . Since polling is not a substitute for discussion, please explain your reasons, taking into account Wikipedia's policy on article titles.

Discussion

 * Any additional comments:

I get no results for "Sook Ching massacre" at Google Ngrams, but I do get results for plain "Sook Ching". A Google search for yields only six results in the top thirty that place "massacre" after Sook Ching. A few other modifiers are used ("operations", "extermination campaign", "bloodbath"), but mostly they just use "Sook Ching". Srnec (talk) 00:48, 6 February 2014 (UTC)

 * Weakly support The Chinese meaning and the conventional usage support the rename, though the current title has the merit emphasizes that it was a massacre. --Yaush (talk) 01:48, 6 February 2014 (UTC)
 * Comment I'm leaning towards opposing the move, but didn't want to rush to judgments. The problem to me is, "Sook ching" (Chinese: 肅清/"suqing"/"su-ch'ing"/"suk-ching"; Japanese: 粛清/"shukusei") literally means "purge". While "purge massacre" indeed is confusing; "sook ching" by itself can also refer to a number of different events (purges) in history, depending on your location in the Chinese-speaking world. In Singapore, "sook ching" clearly refers to this tragedy; however, in Mainland China "sook ching" probably brings to mind the Cultural Revolution; in Taiwan the 228 Incident. Which is why, in Chinese, the word "massacre" was added after "sook ching" to clarify. (I'm checking the Vietnamese and Korean versions and the titles were also constructed this way; the Japanese version has the title "Singaporean Chinese massacre incident".) Timmyshin (talk) 03:11, 6 February 2014 (UTC)
 * "Holocaust" and "Shoah" are no different. In English today, these terms refer to particular events, just like "Reformation" and "Renaissance". Srnec (talk) 12:40, 6 February 2014 (UTC)

 * Question - User:Timmyshin, 粛清 in Japanese can mean many purges, but surely in English, Sook Ching only means one - at least from Google Books. Is this not so? In ictu oculi (talk) 19:27, 6 February 2014 (UTC)
 * Support per Srnec & In ictu oculi's arguments. Timmyshin (talk) 19:35, 6 February 2014 (UTC)
 * The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.

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Suggest to delete A Japanese Humanist section
I suggest to delete "A Japanese Humanist" section.
 * The reputation of Mamoru Shinozaki as A Japanese Humanist is mainly stand on his autobiography (Shinozaki,1982) which was repeatedly criticized by historians and Singapore residents as WP:QUESTIONED. The remark that "he voluntary saved many Chinese people" is also inconsistent with Shinozaki's testimony on Sook Ching trial that "I saved many Chinese people following the direction of Japanese commander Kawamura" which recorded in 1947.
 * His testimony on Sook Ching trial was important in other sense ( his testimony saved some Japanese war criminals). But the reason why it was improtant is not clearly explained in sentences.--UikiHedeo (talk) 11:46, 3 February 2018 (UTC)
 * I see no objection.--UikiHedeo (talk) 08:53, 12 February 2018 (UTC)

It should not be removed because it was the fact that he saved a lot Chinese people. I wite more clearly and precisely.Japanese sincerity (talk) 13:29, 19 February 2018 (UTC)

 * The prescribed period had gone. I think you just reverted my edition neglecting my protest and without further resources. Your edition should be reverted by any third person. --UikiHedeo (talk) 15:24, 24 February 2018 (UTC)

many badly sourced statements
This article uses other anyone-can-edit "wiki" sources several times (like infopedias). Also, several PDF's are not properly attested. Sloppy work. 50.111.36.47 (talk) 07:34, 18 February 2022 (UTC)

 * I agree that the article is in need of lots of cleanup, which I am working on. Links to better sources are appreciated. However, I'm not so sure that the Infopedia source is bad. Its written by the Singapore National Library Board, and appears pretty thoroughly researched. Just because something has "pedia" in the name does not make it inherently good or bad. CaptainEek  Edits Ho Cap'n!⚓ 08:05, 18 February 2022 (UTC)

Crimes against humanity category removal
Crimes against humanity is a specific legal concept. In order to be included in the category, the event (s) must have been prosecuted as a crime against humanity, or at a bare minimum be described as such by most reliable sources. Most of the articles that were formerly in this category did not mention crimes against humanity at all, and the inclusion of the category was purely original research. MediaWiki message delivery (talk) 07:49, 14 February 2024 (UTC)

 * Respectfully, Sook Ching amongst other specific crimes against humanity committed by the Japanese were under the Class C criteria of the International Military Tribunal for the Far East. Senior officials were present at the Tokyo Trials, whereas junior officers and other war criminals who met the criteria of class B and C were tried in a series of other trials held elsewhere. The Singapore trials began in 1946 and tried Japanese War Criminals for their war crimes in British holdings during the war, with Sook Ching among them.
 * I think the issue does come in that as pointed out, Crimes against humanity *is* a specific legal concept, and given the lack of study into the smaller trials that occurred in the East it is more commonplace to just refer to such instances as 'war crimes'. I hope this source suffices since it states the matter very plainly that those on trial for Sook Ching were on trial for crimes against humanity:
 * Arujunan Narayanan. Japanese Atrocities and British Minor War Crimes Trials After World War II in the East. Penerbit UKM, 2006.
 * Any source which lists that those on trial for Sook Ching were Class C war criminals is already sufficient to show they were tried for crimes against humanity.
 * As such I will be restoring the category tag. Relm (talk) 09:50, 3 July 2024 (UTC)

title: Talk:Sook Ching


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User:Guety~enwiki

de:Benutzer:Guety

title: User:Guety~enwiki


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Porous medium

In materials science, a porous medium or a porous material is a material containing pores (voids). The skeletal portion of the material is often called the "matrix" or "frame". The pores are typically filled with a fluid (liquid or gas). The skeletal material is usually a solid, but structures like foams are often also usefully analyzed using concept of porous media.

A porous medium is most often characterised by its porosity. Other properties of the medium (e.g. permeability, tensile strength, electrical conductivity, tortuosity) can sometimes be derived from the respective properties of its constituents (solid matrix and fluid) and the media porosity and pores structure, but such a derivation is usually complex. Even the concept of porosity is only straightforward for a poroelastic medium.

Often both the solid matrix and the pore network (also known as the pore space) are continuous, so as to form two interpenetrating continua such as in a sponge. However, there is also a concept of closed porosity and effective porosity, i.e. the pore space accessible to flow.

Many natural substances such as rocks and soil (e.g. aquifers, petroleum reservoirs), zeolites, biological tissues (e.g. bones, wood, cork), and man made materials such as cements and ceramics can be considered as porous media. Many of their important properties can only be rationalized by considering them to be porous media.

The concept of porous media is used in many areas of applied science and engineering: filtration, mechanics (acoustics, geomechanics, soil mechanics, rock mechanics), engineering (petroleum engineering, bioremediation, construction engineering), geosciences (hydrogeology, petroleum geology, geophysics), biology and biophysics, material science. Two important current fields of application for porous materials are energy conversion and energy storage, where porous materials are essential for superpacitors, (photo-)catalysis, fuel cells, and batteries.

Microscopic and macroscopic
At the microscopic and macroscopic levels, porous media can be classified. At the microscopic scale, the structure is represented statistically by the distribution of pore sizes, the degree of pore interconnection and orientation, the proportion of dead pores, etc. The macroscopic technique makes use of bulk properties that have been averaged at scales far bigger than pore size.

Depending on the goal, these two techniques are frequently employed since they are complimentary. It is obvious that the microscopic description is required to comprehend surface phenomena like the adsorption of macromolecules from polymer solutions and the blocking of pores, whereas the macroscopic approach is frequently quite sufficient for process design where fluid flow, heat, and mass transfer are of highest concern. and the molecular dimensions are significantly smaller than pore size of the porous system.

Fluid flow through porous media
Fluid flow through porous media is a subject of common interest and has emerged a separate field of study. The study of more general behaviour of porous media involving deformation of the solid frame is called poromechanics.

The theory of porous flows has applications in inkjet printing and nuclear waste disposal technologies, among others.

Numerous factors influence fluid flow in porous media, and its fundamental function is to expend energy and create fluid via the wellbore. In flow mechanics via porous medium, the connection between energy and flow rate becomes the most significant issue. The most fundamental law that characterizes this connection is Darcy's law, particularly applicable to fine-porous media. In contrast, Forchheimer's law finds utility in the context of coarse-porous media.

Pore structure models
A representation of the void phase that exists inside porous materials using a set or network of pores. It serves as a structural foundation for the prediction of transport parameters and is employed in the context of pore structure characterisation.

There are many idealized models of pore structures. They can be broadly divided into three categories:
 * networks of capillaries
 * arrays of solid particles (e.g., random close pack of spheres)
 * trimodal

Porous materials often have a fractal-like structure, having a pore surface area that seems to grow indefinitely when viewed with progressively increasing resolution. Mathematically, this is described by assigning the pore surface a Hausdorff dimension greater than 2. Experimental methods for the investigation of pore structures include confocal microscopy and x-ray tomography. Porous materials have found some applications in many engineering fields including automotive sectors.

Laws for porous materials
One of the Laws for porous materials is the generalized Murray's law. The generalized Murray's law is based on optimizing mass transfer by minimizing transport resistance in pores with a given volume, and can be applicable for optimizing mass transfer involving mass variations and chemical reactions involving flow processes, molecule or ion diffusion.

For connecting a parent pipe with radius of r0 to many children pipes with radius of ri, the formula of generalized Murray's law is: $$r_o^a={1 \over 1-X}\sum_{i=1}^Nr_i^a$$, where the X is the ratio of mass variation during mass transfer in the parent pore, the exponent α is dependent on the type of the transfer. For laminar flow α =3; for turbulent flow α =7/3; for molecule or ionic diffusion α =2; etc.

title: Porous medium


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Talk:LCARS

Initial comments
I don't know where the information in this article comes from, but it certainly *isn't* from any 'canon' Star Trek source (ie the series and movies). The POV is also confusing, being partly in-universe. --21:13, 29 Jul 2004 (UTC)

I'm not sure what you mean by 'canon', but the article seems to be written in the style of Star Trek The Next Generation Technical Manual. Given the book is written by the people who 'invented' LCARS it can to some extent be considered as being 'from' Star Trek. Whether it is appropriate for this 'technobabble' to be on Wikipedia is questionable.

 * See canon (fiction) Cburnett 16:30, Jun 15, 2005 (UTC)

Seems to me this page should include some treatment of the FTL (Faster Than Light) core elements of the computer system.

Fair use rationale for Image:LCARS Example.jpg
Image:LCARS Example.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in this Wikipedia article constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.

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BetacommandBot (talk) 14:39, 2 January 2008 (UTC)

Spam
There is no spam found in this article. Is there anything specific any one wishes to point out? I am removing the template for now. MWOAP (talk) 01:51, 8 April 2009 (UTC)

Bedno (talk) 07:53, 27 March 2010 (UTC) The site http://www.lcars.org.uk gives an extreme MALWARE DETECTED warning in Google Chrome browser: "Warning: Visiting this site may harm your computer! The website at www.lcars.org.uk contains elements from the site www.pageranker.org, which appears to host malware – software that can hurt your computer or otherwise operate without your consent. Just visiting a site that contains malware can infect your computer. For detailed information about the problems with these elements, visit the Google Safe Browsing diagnostic page for www.pageranker.org" I've seen the site and its collection is phenomenal, but is perhaps currently unsafe except for very prepared pros, and that precaution should be noted appropriately.
 * Web of Trust, SiteAdvisor, Browser Defender Status and Norton all report www.lcars.org.uk is green and contains no active threats. Same results from www.pageranker.org.ZellDenver (talk) 09:52, 22 April 2010 (UTC)

Correct terminology
The article incorrectly states that LCARS is an operating system, when it is in fact a GUI. Guillep2k (talk) 14:05, 30 November 2010 (UTC)
 * Umm as far as I know, it's an OS & a GUI, the OS deals with the hardware around it. It's not like the use one of the pathetic OS we use today. :P -- DQ  (t)  (e)  22:59, 30 November 2010 (UTC)
 * LCARS Retrieval System. That being the OS. However, usage of the term 'LCARS Interface' suggests it's acceptable to use it as a proper noun when describing the GUI elements of LCARS. I would assume, that due to its popularity and solid design themes, one could use it as either. ZellDenver (talk) 13:20, 31 July 2011 (UTC)

While Linux-based systems seperate the UI from the OS (kernel), others such as MSWindows and Apple's Mac systems there isn't the seperation. Even though technically OS and UI are seperate, in practice it's not usually the case. The iOS vs Android patent lawsuits are based on claims that one OS stole various GUI elements from the other. And since language (except in the case of French) is defined by usage, then in most cases -- such as here -- OS and GUI are practically interchangable terms. — Preceding unsigned comment added by 24.4.155.39 (talk) 04:01, 26 June 2014 (UTC)

Dates
Is anyone able to add approximate dates to the article for when LCARS and PADDs were introduced into the Star Trek world, please? New Thought (talk) 08:53, 11 March 2011 (UTC)

Fiction within fiction?
The lead reads like this: "In the Star Trek fictional universe, LCARS ( /ˈɛlkɑrz/; an acronym for Library Computer Access/Retrieval System) is a fictional computer operating system"

Now I'm pretty sure that's incorrect because if it's a fictional computer in a fictional universe, doesn't that mean that's in fictional in the story? That is to say that in fact it's not a fictional computer in the fictional universe: it's real in the fictional universe. Caledones talk softly, please 22:37, 29 February 2012 (UTC)

Free use of Tricorder name to functioning tech?
I've seen it mentioned on the Internet that Roddenberry's contract allows use of the name to those who apply it to functioning tech. Does anyone have any reputable sources for this information? (ie. a copy of his contract, court transcripts that mention this as fact, etc, etc, etc.) 76.102.199.90 (talk) 10:32, 11 March 2012 (UTC)

Side project
Hey, all -- I'm working in userspace on a broader article on Computers in Star Trek; it's at User:EEMIV/Computers_in_Star_Trek. It still needs some work, but I can imagine a good portion of the content here being merged into a broader article. If you've watchlisted this page and see this message, chances are you may have some ideas and sources appropriate for the article I'm working on; if that's the case, please feel free to contribute in my userspace in the article itself and/or just the talk page. --EEMIV (talk) 05:08, 28 August 2013 (UTC)

Multilanguage
When the expected translate to the great and mighty Russian?

LCARS on Florida TV station
http://commons.wikimedia.org/wiki/File:FEMA_-_28148_-_Photograph_by_Mark_Wolfe_taken_on_02-07-2007_in_Florida.jpg

Might this photo be an interesting addition to the article, given the background illustrations? It is included in the German LCARS article. --Escier (talk) 20:14, 14 January 2015 (UTC)

 * Ha! I think labeling it as LCARS and including in the article, though, is WP:OR in the absence of e.g. someone from that studio design team saying, "Yeah, we tried to imitate that Star Trek style." --EEMIV (talk) 23:49, 14 January 2015 (UTC)

Does Paramount have design patents?
Does anyone know if Paramount has patents on elements of the LCARS "design language"? Jimw338 (talk) 01:38, 22 July 2019 (UTC)
 * That's a really good question. Can one get a design patent for a "design language"? Trivialist (talk) 02:57, 22 July 2019 (UTC)
 * I'm sure Apple would think so.. Jimw338 (talk) 03:49, 30 July 2021 (UTC)

Legal
This section seems to claim that LCARS is copyright CBS. The author(?) of that particular app seems to disagree with this portrayal but has declined providing supporting evidence. I'm not sure how to edit this distinction into the article or even if it's appropriate to do so.

title: Talk:LCARS