The gamecube controller is cool.
A gamepad is a input device for games hold by both hands with both thumbs and fingers used to provide input. The are used on game consoles and the current ones are listed in the input design section.
Buttons can be analog or digital. Digital is the most common. Button on the top of the controll is called face buttons and are pressed down with the thumbs. Digital buttons on the front are called shoulder buttons and if they are analog they are called triggers.
A d-pad is a four-way directional control. Digital is the most common and they can provide eight possible directions.
A small joystick that give a analog value of it's position. Dual sticks is common on gamepads so one stick can be used for movement and one to look around. One variation is a circle pad that works like a control stick but is much more flat. Used on handhelds to take as little space as possible.
Detect the rotation of the gamepad.
Detect physical movement of the gamepad.
This is not a input device but a feedback one. Tiny motors in the gamepad can spin and make the control vibrate. So you can feel the control jump with each shot of your gun.