Arrow key

Cursor movement keys or arrow keys are buttons on a computer keyboard that are either programmed or designated to move the cursor in a specified direction. The term "cursor movement key" is distinct from "arrow key" in that the former term may refer to any of various keys on a computer keyboard designated for cursor movement, whereas "arrow keys" generally refers to one of four specific keys, typically marked with arrows.

Arrow keys are typically located at the bottom of the keyboard to the left side of the numeric keypad, usually arranged in an inverted-T layout but also found in diamond shapes and linear shapes. Arrow keys are commonly used for navigating around documents and for playing games. The inverted-T layout was popularized by the Digital Equipment Corporation LK201 keyboard from 1982.

Before the computer mouse was widespread, arrow keys were the primary way of moving a cursor on screen. Mouse keys is a feature that allows controlling a mouse cursor with arrow keys instead. A feature echoed in the Amiga whereby holding the Amiga key would allow a person to move the pointer with the arrow keys in the Workbench (operating system), but most games require a mouse or joystick. The use of arrow keys in games has come back into fashion from the late 1980s and early 1990s when joysticks were a must, and were usually used in preference to arrow keys with some games not supporting any keys. It can be used instead of WASD keys, to play games using those keys.

The inverted-T layout was popularized by the Digital Equipment Corporation LK201 keyboard from 1982.

Some Commodore 8-bit computers used two keys instead of four, with directions selected using the shift key.

The original Apple Macintosh had no arrow keys at the insistence of Steve Jobs, who felt that people should use the mouse instead. They were deliberately excluded from the Macintosh launch design as a forcing device, acclimating users to the new mouse input device and inducing software developers to conform to mouse-driven design rather than easily porting previous terminal-based software to the new platform. Arrow keys were included in later Apple keyboards. Early models with arrow keys but no middle section (Home, End, etc.) placed them in one line below the right-hand Shift key in an HJKL-like fashion; later versions had a standard inverted-T layout, either in the middle block or as half-height keys at the bottom right of the main keyboard.

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