Tower and Monitor

Tower: The box that holds all the chips such as the motherboard, CPU etc which make the compute work. Without the tower, we'd probably get electrocuted (Ha Ha HA).
Monitor: The screen in which we see what commands are being put in. Also used to see prgrammes that allow video, games and pictures. The monitor puts the V in VISUAL.
Keyboard and Mouse

Mouse: An input device, used to click in commands, selct items and other handy stuff to complicated to do on a keyboard.
Keyboard: An input device used for typing, wheter its typing in of commands or words on programmes such as Microsoft Word or for putting in comands for games and other programmes.