Analog stick

An analog stick, sometimes called a control stick, joystick, or thumbstick is an input device for a controller (often a game controller) that is used for two-dimensional input. An analog stick is a variation of a joystick, consisting of a protrusion from the controller; input is based on the position of this protrusion in relation to the default "center" position. While digital sticks rely on single electrical connections for movement (using internal digital electrical contacts for up, down, left and right), analog sticks use continuous electrical activity running through potentiometers. The analog stick has greatly overtaken the D-pad in both prominence and usage in console video games.

In a video game, an analog stick is often used to move some game object, usually the playable character. It may also be used to rotate the camera, usually around the character. The analog stick can serve a great variety of other functions, depending on the game. Today many analog sticks can also be pushed in like conventional face buttons of a controller, to allow for more functions.

Its use is prevalent in 3D games, where more than 8 directions are needed (which is all that was offered on the d-pad). Using a D-pad in a 3D game greatly limits the ability to move. For example, in a 3D platform game like Super Mario 64, using a D-pad would allow Mario to move forward, backwards, left and right; but nothing in between. Some early 3D games such as Resident Evil overcame this limitation by assigning the Left and Right directions on the D-pad to spin the character instead of making the character move in that direction. This, however, created its own problems as the character was unable to move while spinning, requiring the player to stand in the same spot while changing direction; commonly referred to as "tank controls". With the prevalence of analog sticks, the aforementioned limitations of the D-pad ceased to be an issue.

Two analog sticks offer greater functionality than a single stick. On some modern game controllers, the left stick is positioned to the upper left of the D-pad while the right stick is positioned to the lower left of the face buttons. First-party controllers with this configuration include the Nintendo GameCube controller, Xbox controller, Xbox 360 controller, Xbox One controller, Nintendo Switch Joy-Con (used as one controller) and Nintendo Switch Pro Controller.

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