Ping pong, also called table tennis, is a sport similar to tennis, usually played indoors on a table divided into two sides by a net, making use of small wooden rackets and a miniature ball. Ping pong originated in England in the late 19^th century. Certain circles of the upper class were familiar with the traditional game of lawn tennis and sought to play the game on a smaller scale indoors. They entirely improvised their equipment: stacks of books acted as nets and cigar box lids sufficed as paddles. Balls were made of string, rubber, or sometimes cork. Game manufacturers quickly stepped in to market and sell equipment for the game and thus standardized it. The name for the game, ping pong, came from the sound that early paddles made when striking the ball; other popular names included “whiff whaff” and “gossima” By the early 20^th century, the game was enjoyed in both Europe and the United States and is now a popular sport on an international level.

The equipment in ping pong consists of small wooden rackets (“paddles”), a miniature ball, and a table divided into two sides by a net. There was originally much variation in the types and quality of material used for equipment. Players constructed rackets from cigar box lids or sometimes pieces of parchment stretched over wooden frames attached to handles. String, cork, or rubber were common ball materials and the amount of bounce they had varied from ball to ball. There were no rules dictating the height and length of the table, or the height and thickness of the net. Today, the equipment is standardized by several different governing bodies, including the International Table Tennis Federation and U.S.A. Table Tennis.

• James Gibb, an early British promoter of the game, introduced the modern celluloid ball to the game in 1901. Players considered the bounce of the celluloid ball superior to those of rubber and cork balls, which were far more inconsistent.
• The original diameter of a ping pong ball was 38 mm until 2000, when the ITTF enlarged it to 40mm to make it more visible during televised play.
• A standard ping pong table is nine feet long, five feet wide, and 30 inches high.
• The table is divided in half by a six inch high mesh net.
• In international competition, tables are always either blue or green in color.
• Rackets must be at least 85% wood in international play and are covered in dimpled rubber, which helps to impart spin onto the ball.
• International rules specify that one side of the racket must be red and the other side black.

A game begins when a player serves the ball by tossing it upwards and striking the ball with his/her paddle so that the ball bounces once on his/her side before going over the net and bouncing once on the opponent's side of the net. The opponent must strike the ball back after the first bounce, but before the ball bounces on his/her side again. This begins a “rally.” Game play continues until one of the players is unable to return a shot to the other player's side of the net or when a player strikes the ball but it doesn't bounce on the opponent's side of the table. Either situation would result in a point for the last player to successfully return the ball to the opponent's side. It is illegal to conceal or hide the ball during any point of game play. Players must keep their free hand off of the top of the table while the ball is in play or concede the point.

Despite the simplicity of the rules, ping pong can be a very difficult game to play at top levels. Skilled players can impart a variety of spins to the ball during game play, including backspin, topspin, and sidespin. This is due to the Magnus effect, which can affect any spinning ball, including baseballs and golf balls. These types of spin make it difficult to predict the flight of the ball and thus return the shot. Professional players can also strike a ball in excess of 65 mph.

• In international play, games ended at twenty-one points until 2000, when the ITTF reduced them to eleven. This was intended to speed up pace of play and add excitement to the game.
• Players can hold onto their rackets in any manner they wish, but most players either grip it like a pen or like a hand they are shaking.
• Pairs of players may play in doubles competition. Game play rules are similar to single play, except that a vertical line divides the length of the table in half and players on each team must alternate shots. After five points have been scored, teams switch sides of the table and also switch serves.
• Table tennis became an official Olympic Sport in 1988.
• China has historically dominated international competition.