text:
Biochemistry

Biochemistry or biological chemistry is the study of chemical processes within and relating to living organisms. A sub-discipline of both chemistry and biology, biochemistry may be divided into three fields: structural biology, enzymology, and metabolism. Over the last decades of the 20th century, biochemistry has become successful at explaining living processes through these three disciplines. Almost all areas of the life sciences are being uncovered and developed through biochemical methodology and research. Biochemistry focuses on understanding the chemical basis which allows biological molecules to give rise to the processes that occur within living cells and between cells, in turn relating greatly to the understanding of tissues and organs as well as organism structure and function. Biochemistry is closely related to molecular biology, the study of the molecular mechanisms of biological phenomena.

Much of biochemistry deals with the structures, bonding, functions, and interactions of biological macromolecules such as proteins, nucleic acids, carbohydrates, and lipids. They provide the structure of cells and perform many of the functions associated with life. The chemistry of the cell also depends upon the reactions of small molecules and ions. These can be inorganic (for example, water and metal ions) or organic (for example, the amino acids, which are used to synthesize proteins). The mechanisms used by cells to harness energy from their environment via chemical reactions are known as metabolism. The findings of biochemistry are applied primarily in medicine, nutrition and agriculture. In medicine, biochemists investigate the causes and cures of diseases. Nutrition studies how to maintain health and wellness and also the effects of nutritional deficiencies. In agriculture, biochemists investigate soil and fertilizers with the goal of improving crop cultivation, crop storage, and pest control. In recent decades, biochemical principles and methods have been combined with problem-solving approaches from engineering to manipulate living systems in order to produce useful tools for research, industrial processes, and diagnosis and control of disease—the discipline of biotechnology.

History

At its most comprehensive definition, biochemistry can be seen as a study of the components and composition of living things and how they come together to become life. In this sense, the history of biochemistry may therefore go back as far as the ancient Greeks. However, biochemistry as a specific scientific discipline began sometime in the 19th century, or a little earlier, depending on which aspect of biochemistry is being focused on. Some argued that the beginning of biochemistry may have been the discovery of the first enzyme, diastase (now called amylase), in 1833 by Anselme Payen, while others considered Eduard Buchner's first demonstration of a complex biochemical process alcoholic fermentation in cell-free extracts in 1897 to be the birth of biochemistry. Some might also point as its beginning to the influential 1842 work by Justus von Liebig, Animal chemistry, or, Organic chemistry in its applications to physiology and pathology, which presented a chemical theory of metabolism, or even earlier to the 18th century studies on fermentation and respiration by Antoine Lavoisier. Many other pioneers in the field who helped to uncover the layers of complexity of biochemistry have been proclaimed founders of modern biochemistry. Emil Fischer, who studied the chemistry of proteins, and F. Gowland Hopkins, who studied enzymes and the dynamic nature of biochemistry, represent two examples of early biochemists.

The term "biochemistry" was first used when Vinzenz Kletzinsky (1826–1882) had his "Compendium der Biochemie" printed in Vienna in 1858; it derived from a combination of biology and chemistry. In 1877, Felix Hoppe-Seyler used the term (biochemie in German) as a synonym for physiological chemistry in the foreword to the first issue of Zeitschrift für Physiologische Chemie (Journal of Physiological Chemistry) where he argued for the setting up of institutes dedicated to this field of study. The German chemist Carl Neuberg however is often cited to have coined the word in 1903, while some credited it to Franz Hofmeister.

It was once generally believed that life and its materials had some essential property or substance (often referred to as the "vital principle") distinct from any found in non-living matter, and it was thought that only living beings could produce the molecules of life. In 1828, Friedrich Wöhler published a paper on his serendipitous urea synthesis from potassium cyanate and ammonium sulfate; some regarded that as a direct overthrow of vitalism and the establishment of organic chemistry. However, the Wöhler synthesis has sparked controversy as some reject the death of vitalism at his hands. Since then, biochemistry has advanced, especially since the mid-20th century, with the development of new techniques such as chromatography, X-ray diffraction, dual polarisation interferometry, NMR spectroscopy, radioisotopic labeling, electron microscopy and molecular dynamics simulations. These techniques allowed for the discovery and detailed analysis of many molecules and metabolic pathways of the cell, such as glycolysis and the Krebs cycle (citric acid cycle), and led to an understanding of biochemistry on a molecular level.

Another significant historic event in biochemistry is the discovery of the gene, and its role in the transfer of information in the cell. In the 1950s, James D. Watson, Francis Crick, Rosalind Franklin and Maurice Wilkins were instrumental in solving DNA structure and suggesting its relationship with the genetic transfer of information. In 1958, George Beadle and Edward Tatum received the Nobel Prize for work in fungi showing that one gene produces one enzyme. In 1988, Colin Pitchfork was the first person convicted of murder with DNA evidence, which led to the growth of forensic science. More recently, Andrew Z. Fire and Craig C. Mello received the 2006 Nobel Prize for discovering the role of RNA interference (RNAi) in the silencing of gene expression.

Starting materials: the chemical elements of life

Around two dozen chemical elements are essential to various kinds of biological life. Most rare elements on Earth are not needed by life (exceptions being selenium and iodine), while a few common ones (aluminum and titanium) are not used. Most organisms share element needs, but there are a few differences between plants and animals. For example, ocean algae use bromine, but land plants and animals do not seem to need any. All animals require sodium, but is not an essential element for plants. Plants need boron and silicon, but animals may not (or may need ultra-small amounts).

Just six elements—carbon, hydrogen, nitrogen, oxygen, calcium and phosphorus—make up almost 99% of the mass of living cells, including those in the human body (see composition of the human body for a complete list). In addition to the six major elements that compose most of the human body, humans require smaller amounts of possibly 18 more.

Biomolecules
The 4 main classes of molecules in biochemistry (often called biomolecules) are carbohydrates, lipids, proteins, and nucleic acids. Many biological molecules are polymers: in this terminology, monomers are relatively small macromolecules that are linked together to create large macromolecules known as polymers. When monomers are linked together to synthesize a biological polymer, they undergo a process called dehydration synthesis. Different macromolecules can assemble in larger complexes, often needed for biological activity.

Carbohydrates
Two of the main functions of carbohydrates are energy storage and providing structure. One of the common sugars known as glucose is a carbohydrate, but not all carbohydrates are sugars. There are more carbohydrates on Earth than any other known type of biomolecule; they are used to store energy and genetic information, as well as play important roles in cell to cell interactions and communications.

The simplest type of carbohydrate is a monosaccharide, which among other properties contains carbon, hydrogen, and oxygen, mostly in a ratio of 1:2:1 (generalized formula CnH2nOn, where n is at least 3). Glucose (C6H12O6) is one of the most important carbohydrates; others include fructose (C6H12O6), the sugar commonly associated with the sweet taste of fruits, and deoxyribose (C5H10O4), a component of DNA. A monosaccharide can switch between acyclic (open-chain) form and a cyclic form. The open-chain form can be turned into a ring of carbon atoms bridged by an oxygen atom created from the carbonyl group of one end and the hydroxyl group of another. The cyclic molecule has a hemiacetal or hemiketal group, depending on whether the linear form was an aldose or a ketose.

In these cyclic forms, the ring usually has 5 or 6 atoms. These forms are called furanoses and pyranoses, respectively—by analogy with furan and pyran, the simplest compounds with the same carbon-oxygen ring (although they lack the carbon-carbon double bonds of these two molecules). For example, the aldohexose glucose may form a hemiacetal linkage between the hydroxyl on carbon 1 and the oxygen on carbon 4, yielding a molecule with a 5-membered ring, called glucofuranose. The same reaction can take place between carbons 1 and 5 to form a molecule with a 6-membered ring, called glucopyranose. Cyclic forms with a 7-atom ring called heptoses are rare.

Two monosaccharides can be joined by a glycosidic or ester bond into a disaccharide through a dehydration reaction during which a molecule of water is released. The reverse reaction in which the glycosidic bond of a disaccharide is broken into two monosaccharides is termed hydrolysis. The best-known disaccharide is sucrose or ordinary sugar, which consists of a glucose molecule and a fructose molecule joined. Another important disaccharide is lactose found in milk, consisting of a glucose molecule and a galactose molecule. Lactose may be hydrolysed by lactase, and deficiency in this enzyme results in lactose intolerance.

When a few (around three to six) monosaccharides are joined, it is called an oligosaccharide (oligo- meaning "few"). These molecules tend to be used as markers and signals, as well as having some other uses. Many monosaccharides joined form a polysaccharide. They can be joined in one long linear chain, or they may be branched. Two of the most common polysaccharides are cellulose and glycogen, both consisting of repeating glucose monomers. Cellulose is an important structural component of plant's cell walls and glycogen is used as a form of energy storage in animals.

Sugar can be characterized by having reducing or non-reducing ends. A reducing end of a carbohydrate is a carbon atom that can be in equilibrium with the open-chain aldehyde (aldose) or keto form (ketose). If the joining of monomers takes place at such a carbon atom, the free hydroxy group of the pyranose or furanose form is exchanged with an OH-side-chain of another sugar, yielding a full acetal. This prevents opening of the chain to the aldehyde or keto form and renders the modified residue non-reducing. Lactose contains a reducing end at its glucose moiety, whereas the galactose moiety forms a full acetal with the C4-OH group of glucose. Saccharose does not have a reducing end because of full acetal formation between the aldehyde carbon of glucose (C1) and the keto carbon of fructose (C2).

Lipids

Lipids comprise a diverse range of molecules and to some extent is a catchall for relatively water-insoluble or nonpolar compounds of biological origin, including waxes, fatty acids, fatty-acid derived phospholipids, sphingolipids, glycolipids, and terpenoids (e.g., retinoids and steroids). Some lipids are linear, open-chain aliphatic molecules, while others have ring structures. Some are aromatic (with a cyclic [ring] and planar [flat] structure) while others are not. Some are flexible, while others are rigid.

Lipids are usually made from one molecule of glycerol combined with other molecules. In triglycerides, the main group of bulk lipids, there is one molecule of glycerol and three fatty acids. Fatty acids are considered the monomer in that case, and maybe saturated (no double bonds in the carbon chain) or unsaturated (one or more double bonds in the carbon chain).

Most lipids have some polar character and are largely nonpolar. In general, the bulk of their structure is nonpolar or hydrophobic ("water-fearing"), meaning that it does not interact well with polar solvents like water. Another part of their structure is polar or hydrophilic ("water-loving") and will tend to associate with polar solvents like water. This makes them amphiphilic molecules (having both hydrophobic and hydrophilic portions). In the case of cholesterol, the polar group is a mere –OH (hydroxyl or alcohol).

In the case of phospholipids, the polar groups are considerably larger and more polar, as described below.

Lipids are an integral part of our daily diet. Most oils and milk products that we use for cooking and eating like butter, cheese, ghee etc. are composed of fats. Vegetable oils are rich in various polyunsaturated fatty acids (PUFA). Lipid-containing foods undergo digestion within the body and are broken into fatty acids and glycerol, the final degradation products of fats and lipids. Lipids, especially phospholipids, are also used in various pharmaceutical products, either as co-solubilizers (e.g. in parenteral infusions) or else as drug carrier components (e.g. in a liposome or transfersome).

Proteins

Proteins are very large molecules—macro-biopolymers—made from monomers called amino acids. An amino acid consists of an alpha carbon atom attached to an amino group, –NH2, a carboxylic acid group, –COOH (although these exist as –NH3+ and –COO− under physiologic conditions), a simple hydrogen atom, and a side chain commonly denoted as "–R". The side chain "R" is different for each amino acid of which there are 20 standard ones. It is this "R" group that makes each amino acid different, and the properties of the side chains greatly influence the overall three-dimensional conformation of a protein. Some amino acids have functions by themselves or in a modified form; for instance, glutamate functions as an important neurotransmitter. Amino acids can be joined via a peptide bond. In this dehydration synthesis, a water molecule is removed and the peptide bond connects the nitrogen of one amino acid's amino group to the carbon of the other's carboxylic acid group. The resulting molecule is called a dipeptide, and short stretches of amino acids (usually, fewer than thirty) are called peptides or polypeptides. Longer stretches merit the title proteins. As an example, the important blood serum protein albumin contains 585 amino acid residues.

Proteins can have structural and/or functional roles. For instance, movements of the proteins actin and myosin ultimately are responsible for the contraction of skeletal muscle. One property many proteins have is that they specifically bind to a certain molecule or class of molecules—they may be extremely selective in what they bind. Antibodies are an example of proteins that attach to one specific type of molecule. Antibodies are composed of heavy and light chains. Two heavy chains would be linked to two light chains through disulfide linkages between their amino acids. Antibodies are specific through variation based on differences in the N-terminal domain.

The enzyme-linked immunosorbent assay (ELISA), which uses antibodies, is one of the most sensitive tests modern medicine uses to detect various biomolecules. Probably the most important proteins, however, are the enzymes. Virtually every reaction in a living cell requires an enzyme to lower the activation energy of the reaction. These molecules recognize specific reactant molecules called substrates; they then catalyze the reaction between them. By lowering the activation energy, the enzyme speeds up that reaction by a rate of 1011 or more; a reaction that would normally take over 3,000 years to complete spontaneously might take less than a second with an enzyme. The enzyme itself is not used up in the process and is free to catalyze the same reaction with a new set of substrates. Using various modifiers, the activity of the enzyme can be regulated, enabling control of the biochemistry of the cell as a whole.

The structure of proteins is traditionally described in a hierarchy of four levels. The primary structure of a protein consists of its linear sequence of amino acids; for instance, "alanine-glycine-tryptophan-serine-glutamate-asparagine-glycine-lysine-...". Secondary structure is concerned with local morphology (morphology being the study of structure). Some combinations of amino acids will tend to curl up in a coil called an α-helix or into a sheet called a β-sheet; some α-helixes can be seen in the hemoglobin schematic above. Tertiary structure is the entire three-dimensional shape of the protein. This shape is determined by the sequence of amino acids. In fact, a single change can change the entire structure. The alpha chain of hemoglobin contains 146 amino acid residues; substitution of the glutamate residue at position 6 with a valine residue changes the behavior of hemoglobin so much that it results in sickle-cell disease. Finally, quaternary structure is concerned with the structure of a protein with multiple peptide subunits, like hemoglobin with its four subunits. Not all proteins have more than one subunit.

Ingested proteins are usually broken up into single amino acids or dipeptides in the small intestine and then absorbed. They can then be joined to form new proteins. Intermediate products of glycolysis, the citric acid cycle, and the pentose phosphate pathway can be used to form all twenty amino acids, and most bacteria and plants possess all the necessary enzymes to synthesize them. Humans and other mammals, however, can synthesize only half of them. They cannot synthesize isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. Because they must be ingested, these are the essential amino acids. Mammals do possess the enzymes to synthesize alanine, asparagine, aspartate, cysteine, glutamate, glutamine, glycine, proline, serine, and tyrosine, the nonessential amino acids. While they can synthesize arginine and histidine, they cannot produce it in sufficient amounts for young, growing animals, and so these are often considered essential amino acids.

If the amino group is removed from an amino acid, it leaves behind a carbon skeleton called an α-keto acid. Enzymes called transaminases can easily transfer the amino group from one amino acid (making it an α-keto acid) to another α-keto acid (making it an amino acid). This is important in the biosynthesis of amino acids, as for many of the pathways, intermediates from other biochemical pathways are converted to the α-keto acid skeleton, and then an amino group is added, often via transamination. The amino acids may then be linked together to form a protein.

A similar process is used to break down proteins. It is first hydrolyzed into its component amino acids. Free ammonia (NH3), existing as the ammonium ion (NH4+) in blood, is toxic to life forms. A suitable method for excreting it must therefore exist. Different tactics have evolved in different animals, depending on the animals' needs. Unicellular organisms release the ammonia into the environment. Likewise, bony fish can release ammonia into the water where it is quickly diluted. In general, mammals convert ammonia into urea, via the urea cycle.

In order to determine whether two proteins are related, or in other words to decide whether they are homologous or not, scientists use sequence-comparison methods. Methods like sequence alignments and structural alignments are powerful tools that help scientists identify homologies between related molecules. The relevance of finding homologies among proteins goes beyond forming an evolutionary pattern of protein families. By finding how similar two protein sequences are, we acquire knowledge about their structure and therefore their function.

Nucleic acids

Nucleic acids, so-called because of their prevalence in cellular nuclei, is the generic name of the family of biopolymers. They are complex, high-molecular-weight biochemical macromolecules that can convey genetic information in all living cells and viruses. The monomers are called nucleotides, and each consists of three components: a nitrogenous heterocyclic base (either a purine or a pyrimidine), a pentose sugar, and a phosphate group.

The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). The phosphate group and the sugar of each nucleotide bond with each other to form the backbone of the nucleic acid, while the sequence of nitrogenous bases stores the information. The most common nitrogenous bases are adenine, cytosine, guanine, thymine, and uracil. The nitrogenous bases of each strand of a nucleic acid will form hydrogen bonds with certain other nitrogenous bases in a complementary strand of nucleic acid. Adenine binds with thymine and uracil, thymine binds only with adenine, and cytosine and guanine can bind only with one another. Adenine, thymine, and uracil contain two hydrogen bonds, while hydrogen bonds formed between cytosine and guanine are three.

Aside from the genetic material of the cell, nucleic acids often play a role as second messengers, as well as forming the base molecule for adenosine triphosphate (ATP), the primary energy-carrier molecule found in all living organisms. Also, the nitrogenous bases possible in the two nucleic acids are different: adenine, cytosine, and guanine occur in both RNA and DNA, while thymine occurs only in DNA and uracil occurs in RNA.

Carbohydrates as energy source
Glucose is an energy source in most life forms. For instance, polysaccharides are broken down into their monomers by enzymes (glycogen phosphorylase removes glucose residues from glycogen, a polysaccharide). Disaccharides like lactose or sucrose are cleaved into their two component monosaccharides.

Glycolysis (anaerobic)
Glucose is mainly metabolized by a very important ten-step pathway called glycolysis, the net result of which is to break down one molecule of glucose into two molecules of pyruvate. This also produces a net two molecules of ATP, the energy currency of cells, along with two reducing equivalents of converting NAD+ (nicotinamide adenine dinucleotide: oxidized form) to NADH (nicotinamide adenine dinucleotide: reduced form). This does not require oxygen; if no oxygen is available (or the cell cannot use oxygen), the NAD is restored by converting the pyruvate to lactate (lactic acid) (e.g. in humans) or to ethanol plus carbon dioxide (e.g. in yeast). Other monosaccharides like galactose and fructose can be converted into intermediates of the glycolytic pathway.

Aerobic
In aerobic cells with sufficient oxygen, as in most human cells, the pyruvate is further metabolized. It is irreversibly converted to acetyl-CoA, giving off one carbon atom as the waste product carbon dioxide, generating another reducing equivalent as NADH. The two molecules acetyl-CoA (from one molecule of glucose) then enter the citric acid cycle, producing two molecules of ATP, six more NADH molecules and two reduced (ubi)quinones (via FADH2 as enzyme-bound cofactor), and releasing the remaining carbon atoms as carbon dioxide. The produced NADH and quinol molecules then feed into the enzyme complexes of the respiratory chain, an electron transport system transferring the electrons ultimately to oxygen and conserving the released energy in the form of a proton gradient over a membrane (inner mitochondrial membrane in eukaryotes). Thus, oxygen is reduced to water and the original electron acceptors NAD+ and quinone are regenerated. This is why humans breathe in oxygen and breathe out carbon dioxide. The energy released from transferring the electrons from high-energy states in NADH and quinol is conserved first as proton gradient and converted to ATP via ATP synthase. This generates an additional 28 molecules of ATP (24 from the 8 NADH + 4 from the 2 quinols), totaling to 32 molecules of ATP conserved per degraded glucose (two from glycolysis + two from the citrate cycle). It is clear that using oxygen to completely oxidize glucose provides an organism with far more energy than any oxygen-independent metabolic feature, and this is thought to be the reason why complex life appeared only after Earth's atmosphere accumulated large amounts of oxygen.

Gluconeogenesis
In vertebrates, vigorously contracting skeletal muscles (during weightlifting or sprinting, for example) do not receive enough oxygen to meet the energy demand, and so they shift to anaerobic metabolism, converting glucose to lactate. The combination of glucose from noncarbohydrates origin, such as fat and proteins. This only happens when glycogen supplies in the liver are worn out. The pathway is a crucial reversal of glycolysis from pyruvate to glucose and can use many sources like amino acids, glycerol and Krebs Cycle. Large scale protein and fat catabolism usually occur when those suffer from starvation or certain endocrine disorders. The liver regenerates the glucose, using a process called gluconeogenesis. This process is not quite the opposite of glycolysis, and actually requires three times the amount of energy gained from glycolysis (six molecules of ATP are used, compared to the two gained in glycolysis). Analogous to the above reactions, the glucose produced can then undergo glycolysis in tissues that need energy, be stored as glycogen (or starch in plants), or be converted to other monosaccharides or joined into di- or oligosaccharides. The combined pathways of glycolysis during exercise, lactate's crossing via the bloodstream to the liver, subsequent gluconeogenesis and release of glucose into the bloodstream is called the Cori cycle.

Relationship to other "molecular-scale" biological sciences

Researchers in biochemistry use specific techniques native to biochemistry, but increasingly combine these with techniques and ideas developed in the fields of genetics, molecular biology, and biophysics. There is not a defined line between these disciplines. Biochemistry studies the chemistry required for biological activity of molecules, molecular biology studies their biological activity, genetics studies their heredity, which happens to be carried by their genome. This is shown in the following schematic that depicts one possible view of the relationships between the fields:
 * Biochemistry is the study of the chemical substances and vital processes occurring in live organisms. Biochemists focus heavily on the role, function, and structure of biomolecules. The study of the chemistry behind biological processes and the synthesis of biologically active molecules are applications of biochemistry. Biochemistry studies life at the atomic and molecular level.
 * Genetics is the study of the effect of genetic differences in organisms. This can often be inferred by the absence of a normal component (e.g. one gene). The study of "mutants" – organisms that lack one or more functional components with respect to the so-called "wild type" or normal phenotype. Genetic interactions (epistasis) can often confound simple interpretations of such "knockout" studies.
 * Molecular biology is the study of molecular underpinnings of the biological phenomena, focusing on molecular synthesis, modification, mechanisms and interactions. The central dogma of molecular biology, where genetic material is transcribed into RNA and then translated into protein, despite being oversimplified, still provides a good starting point for understanding the field. This concept has been revised in light of emerging novel roles for RNA.
 * Chemical biology seeks to develop new tools based on small molecules that allow minimal perturbation of biological systems while providing detailed information about their function. Further, chemical biology employs biological systems to create non-natural hybrids between biomolecules and synthetic devices (for example emptied viral capsids that can deliver gene therapy or drug molecules).

Lists

 * Important publications in biochemistry (chemistry)
 * List of biochemistry topics
 * List of biochemists
 * List of biomolecules

title: Biochemistry


text:
Badminton

Badminton is a racquet sport played using racquets to hit a shuttlecock across a net. Although it may be played with larger teams, the most common forms of the game are "singles" (with one player per side) and "doubles" (with two players per side). Badminton is often played as a casual outdoor activity in a yard or on a beach; formal games are played on a rectangular indoor court. Points are scored by striking the shuttlecock with the racquet and landing it within the other team's half of the court.

Each side may only strike the shuttlecock once before it passes over the net. Play ends once the shuttlecock has struck the floor or ground, or if a fault has been called by the umpire, service judge, or (in their absence) the opposing side.

The shuttlecock is a feathered or (in informal matches) plastic projectile that flies differently from the balls used in many other sports. In particular, the feathers create much higher drag, causing the shuttlecock to decelerate more rapidly. Shuttlecocks also have a high top speed compared to the balls in other racquet sports. The flight of the shuttlecock gives the sport its distinctive nature, and in certain languages, e.g. German, the sport is named by reference to this feature i.e. Federball, literally feather-ball.

The game developed in British India from the earlier game of battledore and shuttlecock. European play came to be dominated by Denmark but the game has become very popular in Asia, with recent competitions dominated by China. In 1992, badminton debuted as a Summer Olympic sport with four events: men's singles, women's singles, men's doubles, and women's doubles; mixed doubles was added four years later. At high levels of play, the sport demands excellent fitness: players require aerobic stamina, agility, strength, speed, and precision. It is also a technical sport, requiring good motor coordination and the development of sophisticated racquet movements involving much greater flexibility in the wrist than some other racquet sports.

History

Games employing shuttlecocks have been played for centuries across Eurasia, but the modern game of badminton developed in the mid-19th century among the expatriate officers of British India as a variant of the earlier game of battledore and shuttlecock. ("Battledore" was an older term for "racquet".) Its exact origin remains obscure. The name derives from the Duke of Beaufort's Badminton House in Gloucestershire, but why or when remains unclear. As early as 1860, a London toy dealer named Isaac Spratt published a booklet entitled Badminton Battledore – A New Game, but no copy is known to have survived. An 1863 article in The Cornhill Magazine describes badminton as "battledore and shuttlecock played with sides, across a string suspended some five feet from the ground".

The game originally developed in India among the British expatriates, where it was very popular by the 1870s. Ball badminton, a form of the game played with a wool ball instead of a shuttlecock, was being played in Thanjavur as early as the 1850s and was at first played interchangeably with badminton by the British, the woollen ball being preferred in windy or wet weather.

Early on, the game was also known as Poona or Poonah after the garrison town of Poona (Pune), where it was particularly popular and where the first rules for the game were drawn up in 1873. By 1875, officers returning home had started a badminton club in Folkestone. Initially, the sport was played with sides ranging from 1 to 4 players, but it was quickly established that games between two or four competitors worked the best. The shuttlecocks were coated with India rubber and, in outdoor play, sometimes weighted with lead. Although the depth of the net was of no consequence, it was preferred that it should reach the ground.

The sport was played under the Pune rules until 1887, when J. H. E. Hart of the Bath Badminton Club drew up revised regulations. In 1890, Hart and Bagnel Wild again revised the rules. The Badminton Association of England (BAE) published these rules in 1893 and officially launched the sport at a house called "Dunbar" in Portsmouth on 13 September. The BAE started the first badminton competition, the All England Open Badminton Championships for gentlemen's doubles, ladies' doubles, and mixed doubles, in 1899. Singles competitions were added in 1900 and an England–Ireland championship match appeared in 1904.

England, Scotland, Wales, Canada, Denmark, France, Ireland, the Netherlands, and New Zealand were the founding members of the International Badminton Federation in 1934, now known as the Badminton World Federation. India joined as an affiliate in 1936. The BWF now governs international badminton. Although initiated in England, competitive men's badminton has traditionally been dominated in Europe by Denmark. Worldwide, Asian nations have become dominant in international competition. China, Denmark, Indonesia, Malaysia, India, South Korea, Taiwan (playing as 'Chinese Taipei') and Japan are the nations which have consistently produced world-class players in the past few decades, with China being the greatest force in men's and women's competition recently. Great Britain, where the rules of the modern game were codified, is not among the top powers in the sport, but has had significant Olympic and World success in doubles play, especially mixed doubles.

The game has also become a popular backyard sport in the United States.

Rules
The following information is a simplified summary of badminton rules based on the BWF Statutes publication, Laws of Badminton.

Court

The court is rectangular and divided into halves by a net. Courts are usually marked for both singles and doubles play, although badminton rules permit a court to be marked for singles only. The doubles court is wider than the singles court, but both are of the same length. The exception, which often causes confusion to newer players, is that the doubles court has a shorter serve-length dimension.

The full width of the court is 6.1 m, and in singles this width is reduced to 5.18 m. The full length of the court is 13.4 m. The service courts are marked by a centre line dividing the width of the court, by a short service line at a distance of 1.98 m from the net, and by the outer side and back boundaries. In doubles, the service court is also marked by a long service line, which is 0.76 m from the back boundary.

The net is 1.55 m high at the edges and 1.524 m high in the centre. The net posts are placed over the doubles sidelines, even when singles is played.

The minimum height for the ceiling above the court is not mentioned in the Laws of Badminton. Nonetheless, a badminton court will not be suitable if the ceiling is likely to be hit on a high serve.

Serving

When the server serves, the shuttlecock must pass over the short service line on the opponents' court or it will count as a fault. The server and receiver must remain within their service courts, without touching the boundary lines, until the server strikes the shuttlecock. The other two players may stand wherever they wish, so long as they do not block the vision of the server or receiver.

At the start of the rally, the server and receiver stand in diagonally opposite service courts (see court dimensions). The server hits the shuttlecock so that it would land in the receiver's service court. This is similar to tennis, except that in a badminton serve the whole shuttle must be below 1.15 metres from the surface of the court at the instant of being hit by the server's racket, the shuttlecock is not allowed to bounce and in badminton, the players stand inside their service courts, unlike tennis.

When the serving side loses a rally, the server immediately passes to their opponent(s) (this differs from the old system where sometimes the serve passes to the doubles partner for what is known as a "second serve").

In singles, the server stands in their right service court when their score is even, and in their left service court when their score is odd.

In doubles, if the serving side wins a rally, the same player continues to serve, but he/she changes service courts so that she/he serves to a different opponent each time. If the opponents win the rally and their new score is even, the player in the right service court serves; if odd, the player in the left service court serves. The players' service courts are determined by their positions at the start of the previous rally, not by where they were standing at the end of the rally. A consequence of this system is that each time a side regains the service, the server will be the player who did not serve last time.

Scoring
Each game is played to 21 points, with players scoring a point by winning a rally. This differs from the old system in which players may only win a point on their serve and each game is to 15 points. A match is the best of three games.

If the score ties at 20–20, then the game continues until one side gains a two-point lead (such as 24–22), except when there is a tie at 29–29, in which the game goes to a golden point of 30. Whoever scores this point wins the game.

At the start of a match, the shuttlecock is cast and the side towards which the shuttlecock is pointing serves first. Alternatively, a coin may be tossed, with the winners choosing whether to serve or receive first, or choosing which end of the court to occupy first, and their opponents making the remaining choice.

In subsequent games, the winners of the previous game serve first. Matches are best out of three: a player or pair must win two games (of 21 points each) to win the match. For the first rally of any doubles game, the serving pair may decide who serves and the receiving pair may decide who receives. The players change ends at the start of the second game; if the match reaches a third game, they change ends both at the start of the game and when the leading player's or pair's score reaches 11 points.

Lets
If a let is called, the rally is stopped and replayed with no change to the score. Lets may occur because of some unexpected disturbance such as a shuttlecock landing on a court (having been hit there by players playing in adjacent court) or in small halls the shuttle may touch an overhead rail which can be classed as a let.

If the receiver is not ready when the service is delivered, a let shall be called; yet, if the receiver attempts to return the shuttlecock, the receiver shall be judged to have been ready.

Equipment

Badminton rules restrict the design and size of racquets and shuttlecocks.

Racquets
Badminton racquets are lightweight, with top quality racquets weighing between 70 and 95 g not including grip or strings. They are composed of many different materials ranging from carbon fibre composite (graphite reinforced plastic) to solid steel, which may be augmented by a variety of materials. Carbon fibre has an excellent strength to weight ratio, is stiff, and gives excellent kinetic energy transfer. Before the adoption of carbon fibre composite, racquets were made of light metals such as aluminium. Earlier still, racquets were made of wood. Cheap racquets are still often made of metals such as steel, but wooden racquets are no longer manufactured for the ordinary market, because of their excessive mass and cost. Nowadays, nanomaterials such as carbon nanotubes and fullerenes are added to racquets giving them greater durability.

There is a wide variety of racquet designs, although the laws limit the racquet size and shape. Different racquets have playing characteristics that appeal to different players. The traditional oval head shape is still available, but an isometric head shape is increasingly common in new racquets.

Strings
Badminton strings for racquets are thin, high-performing strings with thicknesses ranging from about 0.62 to 0.73 mm. Thicker strings are more durable, but many players prefer the feel of thinner strings. String tension is normally in the range of 80 to 160 N (18 to 36 lbf). Recreational players generally string at lower tensions than professionals, typically between 80 and 110 N (18 and 25 lbf). Professionals string between about 110 and 160 N (25 and 36 lbf). Some string manufacturers measure the thickness of their strings under tension so they are actually thicker than specified when slack. Ashaway Micropower is actually 0.7mm but Yonex BG-66 is about 0.72mm.

It is often argued that high string tensions improve control, whereas low string tensions increase power. The arguments for this generally rely on crude mechanical reasoning, such as claiming that a lower tension string bed is more bouncy and therefore provides more power. This is, in fact, incorrect, for a higher string tension can cause the shuttle to slide off the racquet and hence make it harder to hit a shot accurately. An alternative view suggests that the optimum tension for power depends on the player: the faster and more accurately a player can swing their racquet, the higher the tension for maximum power. Neither view has been subjected to a rigorous mechanical analysis, nor is there clear evidence in favour of one or the other. The most effective way for a player to find a good string tension is to experiment.

Grip
The choice of grip allows a player to increase the thickness of their racquet handle and choose a comfortable surface to hold. A player may build up the handle with one or several grips before applying the final layer.

Players may choose between a variety of grip materials. The most common choices are PU synthetic grips or towelling grips. Grip choice is a matter of personal preference. Players often find that sweat becomes a problem; in this case, a drying agent may be applied to the grip or hands, sweatbands may be used, the player may choose another grip material or change their grip more frequently.

There are two main types of grip: replacement grips and overgrips. Replacement grips are thicker and are often used to increase the size of the handle. Overgrips are thinner (less than 1 mm), and are often used as the final layer. Many players, however, prefer to use replacement grips as the final layer. Towelling grips are always replacement grips. Replacement grips have an adhesive backing, whereas overgrips have only a small patch of adhesive at the start of the tape and must be applied under tension; overgrips are more convenient for players who change grips frequently, because they may be removed more rapidly without damaging the underlying material.

Shuttlecock
A shuttlecock (often abbreviated to shuttle; also called a birdie) is a high-drag projectile, with an open conical shape: the cone is formed from sixteen overlapping feathers embedded into a rounded cork base. The cork is covered with thin leather or synthetic material. Synthetic shuttles are often used by recreational players to reduce their costs as feathered shuttles break easily. These nylon shuttles may be constructed with either natural cork or synthetic foam base and a plastic skirt.

According to Kathmandu Post the feathers used to make shuttlecocks are plucked from living birds, which causes pain to the birds.

Badminton rules also provide for testing a shuttlecock for the correct speed: "3.1: To test a shuttlecock, hit a full underhand stroke that makes contact with the shuttlecock over the back boundary line. The shuttlecock shall be hit at an upward angle and in a direction parallel to the sidelines.

3.2: A shuttlecock of the correct speed will land not less than 530 mm and not more than 990 mm short of the other back boundary line."

Shoes
Badminton shoes are lightweight with soles of rubber or similar high-grip, non-marking materials.

Compared to running shoes, badminton shoes have little lateral support. High levels of lateral support are useful for activities where lateral motion is undesirable and unexpected. Badminton, however, requires powerful lateral movements. A highly built-up lateral support will not be able to protect the foot in badminton; instead, it will encourage catastrophic collapse at the point where the shoe's support fails, and the player's ankles are not ready for the sudden loading, which can cause sprains. For this reason, players should choose badminton shoes rather than general trainers or running shoes, because proper badminton shoes will have a very thin sole, lower a person's centre of gravity, and therefore result in fewer injuries. Players should also ensure that they learn safe and proper footwork, with the knee and foot in alignment on all lunges. This is more than just a safety concern; proper footwork is also critical in order to move effectively around the court.

Strokes
Badminton offers a wide variety of basic strokes, and players require a high level of skill to perform all of them effectively. All strokes can be played either forehand or backhand. A player's forehand side is the same side as their playing hand: for a right-handed player, the forehand side is their right side and the backhand side is their left side. Forehand strokes are hit with the front of the hand leading (like hitting with the palm), whereas backhand strokes are hit with the back of the hand leading (like hitting with the knuckles). Players frequently play certain strokes on the forehand side with a backhand hitting action, and vice versa.

In the forecourt and midcourt, most strokes can be played equally effectively on either the forehand or backhand side; but in the rear court, players will attempt to play as many strokes as possible on their forehands, often preferring to play a round-the-head forehand overhead (a forehand "on the backhand side") rather than attempt a backhand overhead. Playing a backhand overhead has two main disadvantages. First, the player must turn their back to their opponents, restricting their view of them and the court. Second, backhand overheads cannot be hit with as much power as forehands: the hitting action is limited by the shoulder joint, which permits a much greater range of movement for a forehand overhead than for a backhand. The backhand clear is considered by most players and coaches to be the most difficult basic stroke in the game, since the precise technique is needed in order to muster enough power for the shuttlecock to travel the full length of the court. For the same reason, backhand smashes tend to be weak.

Position of the shuttlecock and receiving player

The choice of stroke depends on how near the shuttlecock is to the net, whether it is above net height, and where an opponent is currently positioned: players have much better attacking options if they can reach the shuttlecock well above net height, especially if it is also close to the net. In the forecourt, a high shuttlecock will be met with a net kill, hitting it steeply downwards and attempting to win the rally immediately. This is why it is best to drop the shuttlecock just over the net in this situation. In the midcourt, a high shuttlecock will usually be met with a powerful smash, also hitting downwards and hoping for an outright winner or a weak reply. Athletic jump smashes, where players jump upwards for a steeper smash angle, are a common and spectacular element of elite men's doubles play. In the rearcourt, players strive to hit the shuttlecock while it is still above them, rather than allowing it to drop lower. This overhead hitting allows them to play smashes, clears (hitting the shuttlecock high and to the back of the opponents' court), and drop shots (hitting the shuttlecock softly so that it falls sharply downwards into the opponents' forecourt). If the shuttlecock has dropped lower, then a smash is impossible and a full-length, high clear is difficult.

Vertical position of the shuttlecock
When the shuttlecock is well below net height, players have no choice but to hit upwards. Lifts, where the shuttlecock is hit upwards to the back of the opponents' court, can be played from all parts of the court. If a player does not lift, their only remaining option is to push the shuttlecock softly back to the net: in the forecourt, this is called a net shot; in the midcourt or rear court, it is often called a push or block.

When the shuttlecock is near to net height, players can hit drives, which travel flat and rapidly over the net into the opponents' rear midcourt and rear court. Pushes may also be hit flatter, placing the shuttlecock into the front midcourt. Drives and pushes may be played from the midcourt or forecourt, and are most often used in doubles: they are an attempt to regain the attack, rather than choosing to lift the shuttlecock and defend against smashes. After a successful drive or push, the opponents will often be forced to lift the shuttlecock.

Spin
Balls may be spun to alter their bounce (for example, topspin and backspin in tennis) or trajectory, and players may slice the ball (strike it with an angled racquet face) to produce such spin. The shuttlecock is not allowed to bounce, but slicing the shuttlecock does have applications in badminton. (See Basic strokes for an explanation of technical terms.)
 * Slicing the shuttlecock from the side may cause it to travel in a different direction from the direction suggested by the player's racquet or body movement. This is used to deceive opponents.
 * Slicing the shuttlecock from the side may cause it to follow a slightly curved path (as seen from above), and the deceleration imparted by the spin causes sliced strokes to slow down more suddenly towards the end of their flight path. This can be used to create drop shots and smashes that dip more steeply after they pass the net.
 * When playing a net shot, slicing underneath the shuttlecock may cause it to turn over itself (tumble) several times as it passes the net. This is called a spinning net shot or tumbling net shot. The opponent will be unwilling to address the shuttlecock until it has corrected its orientation.

Due to the way that its feathers overlap, a shuttlecock also has a slight natural spin about its axis of rotational symmetry. The spin is in a counter-clockwise direction as seen from above when dropping a shuttlecock. This natural spin affects certain strokes: a tumbling net shot is more effective if the slicing action is from right to left, rather than from left to right.

Biomechanics
Badminton biomechanics have not been the subject of extensive scientific study, but some studies confirm the minor role of the wrist in power generation and indicate that the major contributions to power come from internal and external rotations of the upper and lower arm. Recent guides to the sport thus emphasize forearm rotation rather than wrist movements.

The feathers impart substantial drag, causing the shuttlecock to decelerate greatly over distance. The shuttlecock is also extremely aerodynamically stable: regardless of initial orientation, it will turn to fly cork-first and remain in the cork-first orientation.

One consequence of the shuttlecock's drag is that it requires considerable power to hit it the full length of the court, which is not the case for most racquet sports. The drag also influences the flight path of a lifted (lobbed) shuttlecock: the parabola of its flight is heavily skewed so that it falls at a steeper angle than it rises. With very high serves, the shuttlecock may even fall vertically.

Other factors

When defending against a smash, players have three basic options: lift, block, or drive. In singles, a block to the net is the most common reply. In doubles, a lift is the safest option but it usually allows the opponents to continue smashing; blocks and drives are counter-attacking strokes but may be intercepted by the smasher's partner. Many players use a backhand hitting action for returning smashes on both the forehand and backhand sides because backhands are more effective than forehands at covering smashes directed to the body. Hard shots directed towards the body are difficult to defend.

The service is restricted by the Laws and presents its own array of stroke choices. Unlike in tennis, the server's racquet must be pointing in a downward direction to deliver the serve so normally the shuttle must be hit upwards to pass over the net. The server can choose a low serve into the forecourt (like a push), or a lift to the back of the service court, or a flat drive serve. Lifted serves may be either high serves, where the shuttlecock is lifted so high that it falls almost vertically at the back of the court, or flick serves, where the shuttlecock is lifted to a lesser height but falls sooner.

Deception
Once players have mastered these basic strokes, they can hit the shuttlecock from and to any part of the court, powerfully and softly as required. Beyond the basics, however, badminton offers rich potential for advanced stroke skills that provide a competitive advantage. Because badminton players have to cover a short distance as quickly as possible, the purpose of many advanced strokes is to deceive the opponent, so that either they are tricked into believing that a different stroke is being played, or they are forced to delay their movement until they actually sees the shuttle's direction. "Deception" in badminton is often used in both of these senses. When a player is genuinely deceived, they will often lose the point immediately because they cannot change their direction quickly enough to reach the shuttlecock. Experienced players will be aware of the trick and cautious not to move too early, but the attempted deception is still useful because it forces the opponent to delay their movement slightly. Against weaker players whose intended strokes are obvious, an experienced player may move before the shuttlecock has been hit, anticipating the stroke to gain an advantage.

Slicing and using a shortened hitting action are the two main technical devices that facilitate deception. Slicing involves hitting the shuttlecock with an angled racquet face, causing it to travel in a different direction than suggested by the body or arm movement. Slicing also causes the shuttlecock to travel more slowly than the arm movement suggests. For example, a good crosscourt sliced drop shot will use a hitting action that suggests a straight clear or a smash, deceiving the opponent about both the power and direction of the shuttlecock. A more sophisticated slicing action involves brushing the strings around the shuttlecock during the hit, in order to make the shuttlecock spin. This can be used to improve the shuttle's trajectory, by making it dip more rapidly as it passes the net; for example, a sliced low serve can travel slightly faster than a normal low serve, yet land on the same spot. Spinning the shuttlecock is also used to create spinning net shots (also called tumbling net shots), in which the shuttlecock turns over itself several times (tumbles) before stabilizing; sometimes the shuttlecock remains inverted instead of tumbling. The main advantage of a spinning net shot is that the opponent will be unwilling to address the shuttlecock until it has stopped tumbling, since hitting the feathers will result in an unpredictable stroke. Spinning net shots are especially important for high-level singles players.

The lightness of modern racquets allows players to use a very short hitting action for many strokes, thereby maintaining the option to hit a powerful or a soft stroke until the last possible moment. For example, a singles player may hold their racquet ready for a net shot, but then flick the shuttlecock to the back instead with a shallow lift when they notice the opponent has moved before the actual shot was played. A shallow lift takes less time to reach the ground and as mentioned above a rally is over when the shuttlecock touches the ground. This makes the opponent's task of covering the whole court much more difficult than if the lift was hit higher and with a bigger, obvious swing. A short hitting action is not only useful for deception: it also allows the player to hit powerful strokes when they have no time for a big arm swing. A big arm swing is also usually not advised in badminton because bigger swings make it more difficult to recover for the next shot in fast exchanges. The use of grip tightening is crucial to these techniques, and is often described as finger power. Elite players develop finger power to the extent that they can hit some power strokes, such as net kills, with less than a 10 cm racquet swing.

It is also possible to reverse this style of deception, by suggesting a powerful stroke before slowing down the hitting action to play a soft stroke. In general, this latter style of deception is more common in the rear court (for example, drop shots disguised as smashes), whereas the former style is more common in the forecourt and midcourt (for example, lifts disguised as net shots).

Deception is not limited to slicing and short hitting actions. Players may also use double motion, where they make an initial racquet movement in one direction before withdrawing the racquet to hit in another direction. Players will often do this to send opponents in the wrong direction. The racquet movement is typically used to suggest a straight angle but then play the stroke crosscourt, or vice versa. Triple motion is also possible, but this is very rare in actual play. An alternative to double motion is to use a racquet head fake, where the initial motion is continued but the racquet is turned during the hit. This produces a smaller change in direction but does not require as much time.

Strategy
To win in badminton, players need to employ a wide variety of strokes in the right situations. These range from powerful jumping smashes to delicate tumbling net returns. Often rallies finish with a smash, but setting up the smash requires subtler strokes. For example, a net shot can force the opponent to lift the shuttlecock, which gives an opportunity to smash. If the net shot is tight and tumbling, then the opponent's lift will not reach the back of the court, which makes the subsequent smash much harder to return.

Deception is also important. Expert players prepare for many different strokes that look identical and use slicing to deceive their opponents about the speed or direction of the stroke. If an opponent tries to anticipate the stroke, they may move in the wrong direction and may be unable to change their body momentum in time to reach the shuttlecock.

Singles
Since one person needs to cover the entire court, singles tactics are based on forcing the opponent to move as much as possible; this means that singles strokes are normally directed to the corners of the court. Players exploit the length of the court by combining lifts and clears with drop shots and net shots. Smashing tends to be less prominent in singles than in doubles because the smasher has no partner to follow up their effort and is thus vulnerable to a skillfully placed return. Moreover, frequent smashing can be exhausting in singles where the conservation of a player's energy is at a premium. However, players with strong smashes will sometimes use the shot to create openings, and players commonly smash weak returns to try to end rallies.

In singles, players will often start the rally with a forehand high serve or with a flick serve. Low serves are also used frequently, either forehand or backhand. Drive serves are rare.

At high levels of play, singles demand extraordinary fitness. Singles is a game of patient positional manoeuvring, unlike the all-out aggression of doubles.

Doubles

Both pairs will try to gain and maintain the attack, smashing downwards when the opportunity arises. Whenever possible, a pair will adopt an ideal attacking formation with one player hitting down from the rear court, and their partner in the midcourt intercepting all smash returns except the lift. If the rear court attacker plays a drop shot, their partner will move into the forecourt to threaten the net reply. If a pair cannot hit downwards, they will use flat strokes in an attempt to gain the attack. If a pair is forced to lift or clear the shuttlecock, then they must defend: they will adopt a side-by-side position in the rear midcourt, to cover the full width of their court against the opponents' smashes. In doubles, players generally smash to the middle ground between two players in order to take advantage of confusion and clashes.

At high levels of play, the backhand serve has become popular to the extent that forehand serves have become fairly rare at a high level of play. The straight low serve is used most frequently, in an attempt to prevent the opponents gaining the attack immediately. Flick serves are used to prevent the opponent from anticipating the low serve and attacking it decisively.

At high levels of play, doubles rallies are extremely fast. Men's doubles are the most aggressive form of badminton, with a high proportion of powerful jump smashes and very quick reflex exchanges. Because of this, spectator interest is sometimes greater for men's doubles than for singles.

Mixed doubles

In mixed doubles, both pairs typically try to maintain an attacking formation with the woman at the front and the man at the back. This is because the male players are usually substantially stronger, and can, therefore, produce smashes that are more powerful. As a result, mixed doubles require greater tactical awareness and subtler positional play. Clever opponents will try to reverse the ideal position, by forcing the woman towards the back or the man towards the front. In order to protect against this danger, mixed players must be careful and systematic in their shot selection.

At high levels of play, the formations will generally be more flexible: the top women players are capable of playing powerfully from the back-court, and will happily do so if required. When the opportunity arises, however, the pair will switch back to the standard mixed attacking position, with the woman in front and men in the back.

Governing bodies
The Badminton World Federation (BWF) is the internationally recognized governing body of the sport responsible for the regulation of tournaments and approaching fair play. Five regional confederations are associated with the BWF:

 * Asia: Badminton Asia Confederation (BAC)
 * Africa: Badminton Confederation of Africa (BCA)
 * Americas: Badminton Pan Am (North America and South America belong to the same confederation; BPA)
 * Europe: Badminton Europe (BE)
 * Oceania: Badminton Oceania (BO)

Competitions
The BWF organizes several international competitions, including the Thomas Cup, the premier men's international team event first held in 1948–1949, and the Uber Cup, the women's equivalent first held in 1956–1957. The competitions now take place once every two years. More than 50 national teams compete in qualifying tournaments within continental confederations for a place in the finals. The final tournament involves 12 teams, following an increase from eight teams in 2004. It was further increased to 16 teams in 2012.

The Sudirman Cup, a gender-mixed international team event held once every two years, began in 1989. Teams are divided into seven levels based on the performance of each country. To win the tournament, a country must perform well across all five disciplines (men's doubles and singles, women's doubles and singles, and mixed doubles). Like association football (soccer), it features a promotion and relegation system at every level. However, the system was last used in 2009 and teams competing will now be grouped by world rankings.

Badminton was a demonstration event at the 1972 and 1988 Summer Olympics. It became an official Summer Olympic sport at the Barcelona Olympics in 1992 and its gold medals now generally rate as the sport's most coveted prizes for individual players.

In the BWF World Championships, first held in 1977, currently only the highest-ranked 64 players in the world, and a maximum of four from each country can participate in any category. Therefore it's not an "open" format. In both the BWF World and the Olympic competitions restrictions on the number of participants from any one country have caused some controversy, because they result in excluding some world elite level players from the strongest badminton nations. The Thomas, Uber, and Sudirman Cups, the Olympics, and the BWF World (and World Junior Championships), are all categorized as level one tournaments.

At the start of 2007, the BWF introduced a new tournament structure for the highest level tournaments aside from those in level one: the BWF Super Series. This "level two" tournament series is a circuit for the world's elite players, staging twelve open tournaments around the world with 32 players (half the previous limit). The players collect points that determine whether they can play in Super Series Finals held at the year-end. Among the tournaments in this series is the venerable All-England Championships, first held in 1900, which was once considered the unofficial world championships of the sport.

Level three tournaments consist of Grand Prix Gold and Grand Prix event. Top players can collect the world ranking points and enable them to play in the BWF Super Series open tournaments. These include the regional competitions in Asia (Badminton Asia Championships) and Europe (European Badminton Championships), which produce the world's best players as well as the Pan America Badminton Championships.

The level four tournaments, known as International Challenge, International Series, and Future Series, encourage participation by junior players.

Comparison with tennis
Badminton is frequently compared to tennis due to several qualities. The following is a list of manifest differences:
 * Scoring: In badminton, a match is played best of 2 of 3 games, with each game played up to 21 points. In tennis a match is played best of 3 or 5 sets, each set consisting of 6 games and each game ends when one player wins 4 points or wins two consecutive points at deuce points. If both teams are tied at "game point", they must play until one team achieves a two-point advantage. However, at 29–all, whoever scores the golden point will win. In tennis, if the score is tied 6–6 in a set, a tiebreaker will be played, which ends once a player reaches 7 points or when one player has a two-point advantage.
 * In tennis, the ball may bounce once before the point ends; in badminton, the rally ends once the shuttlecock touches the floor.
 * In tennis, the serve is dominant to the extent that the server is expected to win most of their service games (at advanced level & onwards); a break of service, where the server loses the game, is of major importance in a match. In badminton, a server has far less an advantage and is unlikely to score an ace (unreturnable serve).
 * In tennis, the server has two chances to hit a serve into the service box; in badminton, the server is allowed only one attempt.
 * A tennis court is approximately twice the length and width of a badminton court.
 * Tennis racquets are about four times as heavy as badminton racquets, 10 to 12 oz versus 2 to 3 oz. Tennis balls are more than eleven times heavier than shuttlecocks, 57 g versus 5 g.
 * The fastest recorded tennis stroke is Samuel Groth's 163.4 mph serve, whereas the fastest badminton stroke during gameplay was Mads Pieler Kolding's 264.7 mi/h recorded smash at a Badminton Premier League match.

Statistics such as the smash speed, above, prompt badminton enthusiasts to make other comparisons that are more contentious. For example, it is often claimed that badminton is the fastest racquet sport. Although badminton holds the record for the fastest initial speed of a racquet sports projectile, the shuttlecock decelerates substantially faster than other projectiles such as tennis balls. In turn, this qualification must be qualified by consideration of the distance over which the shuttlecock travels: a smashed shuttlecock travels a shorter distance than a tennis ball during a serve.

While fans of badminton and tennis often claim that their sport is the more physically demanding, such comparisons are difficult to make objectively because of the differing demands of the games. No formal study currently exists evaluating the physical condition of the players or demands during gameplay.

Badminton and tennis techniques differ substantially. The lightness of the shuttlecock and of badminton racquets allows badminton players to make use of the wrist and fingers much more than tennis players; in tennis, the wrist is normally held stable, and playing with a mobile wrist may lead to injury. For the same reasons, badminton players can generate power from a short racquet swing: for some strokes such as net kills, an elite player's swing may be less than 5 cm. For strokes that require more power, a longer swing will typically be used, but the badminton racquet swing will rarely be as long as a typical tennis swing.

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

title: Badminton