Game Pads are a type of input device which is a controller that connects to the computer and has multiple buttons for manipulating specific actions. They require installation software. Joysticks are a type of gaming pad which is just one stick with multiple buttons used for simulation games. They range in price, configuration and operational requirements so special considerations should be given to assure they work with the targeted computer systems. Digitizers is a tablet-like surface area device that allows you to draw on your computer screen using an input device like pen which itself has mouse-like capabilities such as right-clicking. They are plug-n-play but do come with product software so they will require some installation setup to run properly.