Gamepads generally feature a set of buttons handled with the right thumb and a direction controller handled with the left. The direction controller has traditionally been a four-way digital cross (also named a joypad, or alternatively a d-pad, and never called arrow keys), but most modern controllers additionally (or as a substitute) feature one or more analog sticks.
Some common additions to the standard pad include shoulder buttons (also called "bumpers") and triggers placed along the edges of the pad (shoulder buttons are usually digital, i.e. merely on/off, while triggers are usually analog); centrally placed start, select, and mode buttons, and an internal motor to provide force feedback.
There are programmable joysticks that can emulate keyboard input. Generally they have been made to circumvent the lack of joystick support in some computer games, i.e. the Belkin Nostromo SpeedPad n52. There are several programs that emulate keyboard and mouse input with a gamepad such as the free and open-source cross-platform software antimicro, Enjoy2, or proprietary commercial solutions such as JoyToKey, Xpadder, and Pinnacle Game Profiler.
The 1962 video game Spacewar! initially used toggle switches built into the computer readout display to control the game. These switches were awkward and uncomfortable to use, so Alan Kotok and Bob Saunders built and wired in a detached control device for the game. This device has been called the earliest gamepad.
It would take many years for the gamepad to rise to prominence, as during the 1970s and the early 1980s joysticks and paddles were the dominant video game controllers, though several Atari joystick port-compatible pushbutton controllers were also available. The third generation of video games saw many major changes, and the eminence of gamepads in the video game market.