In chess, a fork is a tactic that uses a single piece to attack multiple pieces at the same time. The attacker usually hopes to gain material by capturing one of the opponent's pieces. The defender often finds himself in a difficult position in which he cannot counter all threats. The attacking piece is known as the forking piece. Conversely, the pieces that the forking piece is attacking are said to be forked.

A piece that is defended can still be forked. In this situation, material gain is still possible, if the forking piece has lower value.

It is also worth noting that the targets of the fork do not both have to be pieces, although this is known as a double attack. One or more of the targets may be mate threats (for example, forking a loose knight and setting up a battery of queen and bishop to create a mating threat) or implied threats (for example, a knight may be on the way to forking queen and rook while attacking a lose minor piece), while forking the loose bishop.

The type of fork is commonly named after the type of forking piece. For example, in a knight fork, a knight moves to attack two or more opponent's pieces in the same move. Any type of piece may perform a fork, including a king, and any type of piece can be forked. A fork is most effective, when it is forced or when the king is under attack.

As a piece of cutlery or kitchenware, a fork is a tool consisting of a handle with several narrow tines on one end. The fork, as an eating utensil, has been a feature primarily of the West, whereas in East Asia chopsticks have been more prevalent. Today, forks are increasingly available throughout East Asia. The utensil (usually metal) is used to lift food to the mouth or to hold food in place while cooking or cutting it. Food can be lifted either by spearing it on the tines, or by holding it on top of the tines, which are often curved slightly. For this latter function, in the American style of fork etiquette, the fork is held with tines curving up; however, in continental style, the fork is held with the tines curving down.^{[citation needed]} A fork is also shaped in the form of a trident but curved at the joint of the handle to the points.

Though the fork's early history is obscure, the fork as a kitchen and dining utensil is generally believed to have originated in the Roman Empire, or perhaps in Ancient Greece. The personal table fork most likely originated in the Eastern Roman, or Byzantine, Empire. Its use spread to what is now the Middle East during the first millennium CE and then spread into southern Europe during the second millennium. It did not become common in northern Europe until the 18th century and was not common in North America until the 19th century.

Chess is a two-player board game played on a chessboard, a square checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.

Each player begins the game with sixteen pieces: one king, one queen, two rooks, two knights, two bishops, and eight pawns, each of these types of pieces moving differently. Pieces are used to attack and capture the opponent's pieces. The object of the game is to 'checkmate' the opponent's king by placing it under an inescapable threat of capture. In addition to checkmate, the game can be won by the voluntary resignation of one's opponent, which may occur when too much material is lost, or if checkmate appears unavoidable. A game may also result in a draw in several ways, where neither player wins. The course of the game is divided in three phases. The beginning of the game is called the opening (with the development of pieces). The opening yields to the phase called the middlegame. The last phase is the endgame, generally characterized by the disappearance of queens.