Fast keypad system is a new input device that makes functions utilized frequently be used for users by customizing them. We let users approached to selected functions speedily and easily by applications after applying them to the Fast keypad system. Also, continuous works on previous contents become to be available by storing them having been done by Fast keypad into the device even in case of moving them into other computer after considering cases of using N set computers by users. Finally, this prevented troubles by additional input devices besides keyboard and mouse by having mouse control functions built-in.