Input/Output Gate: What it says on the tin. It is a lever, that when you flick it, gives a current on the green wire.
NOT Gate (Inverter): It does the opposite of Input/Output. When you flick the lever on, it goes off, and off, it goes on. This is more useful with buttons, (Example a piston door).
AND Gate: You have to turn both levers on to get it to work. One or neither won't do it.
OR Gate: Press either lever (Or both) turns it on.
XOR Gate: I don't even...
*I will finish this after school. Feel free to edit this*