A paddle is a game controller

Game controller

A game controller is a device used with games or entertainment systems used to control a playable character or object, or otherwise provide input in a computer game. A controller is typically connected to a game console or computer by means of a wire, cord or nowadays, by means of wireless connection...

 with a round wheel and one or more fire buttons, where the wheel is typically used to control movement of the player object along one axis of the video screen. A paddle controller rotates through a fixed arc (usually about 330 degrees); it has a stop at each end.

Design

The paddle wheel is usually mechanically coupled to a potentiometer

Potentiometer

A potentiometer , informally, a pot, is a three-terminal resistor with a sliding contact that forms an adjustable voltage divider. If only two terminals are used , it acts as a variable resistor or rheostat. Potentiometers are commonly used to control electrical devices such as volume controls on...

, so as to generate an output voltage level varying with the wheel's angle relative to a fixed reference position. A paddle is thus an absolute position controller. That is, without any previous knowledge, the sensor can be read and the result directly indicates the position of the paddle knob. This is in contrast to a quadrature encoder-based device or "spinner".

Where employed

Paddles first appeared in video arcade games with Atari Inc.'s Pong

Pong

Pong is one of the earliest arcade video games, and is a tennis sports game featuring simple two-dimensional graphics. While other arcade video games such as Computer Space came before it, Pong was one of the first video games to reach mainstream popularity...

in 1972, while the first console to use paddles was Magnavox's Odyssey

Odyssey

The Odyssey is one of two major ancient Greek epic poems attributed to Homer. It is, in part, a sequel to the Iliad, the other work ascribed to Homer. The poem is fundamental to the modern Western canon, and is the second—the Iliad being the first—extant work of Western literature...

 that same year. The Atari 2600

Atari 2600

The Atari 2600 is a video game console released in October 1977 by Atari, Inc. It is credited with popularizing the use of microprocessor-based hardware and cartridges containing game code, instead of having non-microprocessor dedicated hardware with all games built in...

 used paddles for several of its games, as did early home computers such as the Commodore VIC-20

Commodore VIC-20

The VIC-20 is an 8-bit home computer which was sold by Commodore Business Machines. The VIC-20 was announced in 1980, roughly three years after Commodore's first personal computer, the PET...

. True (potentiometer-based) paddles are almost never employed any more because they stop reading accurately when the potentiometer contacts get dirty or worn, because turning them too far can break them and because they require more-expensive analog sensing, whereas quadrature encoder-based controllers can be sensed digitally. Any recent game that has paddle-type control uses a quadrature encoder instead, even if the game uses paddles on screen (like Arkanoid

Arkanoid

is an arcade game developed by Taito in 1986. It is based upon Atari's Breakout games of the 1970s. The title refers to a doomed "mothership" from which the player's ship, the Vaus, escapes.-Overview:...

).

Games

Some famous video games using paddles are Pong, Breakout, and Night Driver

Night Driver

Night Driver is a 1976 arcade game by Atari Inc. It was one of the earliest first-person racing games, and is believed to be one of the first published games to display real-time first-person graphics....

. The reason for the name paddles for this type of game controller is that the first game that used it, Pong, was a video game simulation of table tennis

Table tennis

Table tennis, also known as ping-pong, is a sport in which two or four players hit a lightweight, hollow ball back and forth using table tennis rackets. The game takes place on a hard table divided by a net...

, whose racquets are commonly called paddles. Even though the simulated paddles appeared on-screen (as small line segments), it was the hand controllers used to move the line segments that actually came to bear the name.

Similar controllers

On the Atari 2600, the paddle controllers look very similar to the driving controllers. Paddle controllers come in pairs both connecting to a single controller port. Paddle controllers also rotate just under one full rotation before hitting a hard stop. Finally, they have a picture of a tennis racquet and the word "paddle" on it. Because two controllers connect to each port and the 2600 has two controller ports, four players simultaneously can play in games that support it. The Atari paddles are also compatible with the Atari 800 home computer, with its four game controller ports. This would allow eight paddles in simultaneous play, however it is doubtful there are any games released that support this many players.

Atari also offered driving controllers for use with games like Indy 500, which requires wheels that can spin around continuously in one direction. Driving controllers have a picture of a car and the word "driving" on it and a single controller attaches to each controller port. The driving controller is not compatible with paddle games. Like a mechanical computer mouse

Mouse (computing)

In computing, a mouse is a pointing device that functions by detecting two-dimensional motion relative to its supporting surface. Physically, a mouse consists of an object held under one of the user's hands, with one or more buttons...

, the driving controller is a quadrature encoder-based device and thus only sensed relative position, not absolute position. This controller is functionally identical to the spin-dial controller used in Atari's Tempest arcade game. Since only one controller attaches to each port, only two people can play driving games simultaneously.

Several similar relative spinner controllers have emerged as part of the home-built arcade cabinet

Arcade cabinet

A video game arcade cabinet, also known as a video arcade machine or video coin-op, is the housing within which a video arcade game's hardware resides. Most cabinets designed since the mid-1980s conform to the JAMMA wiring standard...

scene to facilitate play of such games as Tempest, including spinners from Oscar Controls and the SlikStik Tornado spinner. These devices are typically made to plug directly into a computer as a single-axis mouse.