A two way light switch is the most typically used light switch in a house. You use two of these switches, for instance at two different entrances to a room, to switch on one light or lighting circuit.
You can recognise a two way light switch from the back. It will have a COM, L1 and L2 connection terminal.
Can I use a two way light switch for one way switching?
Yes, you can use a two way light switch for one way switching, in fact one way light switches are relatively unused these days, as the difference in cost between a one way and two way switch is minimal, so most electricians simply use a two way switch for both purposes.
The only difference for wiring a one way switch is you connect the COM and L1 connection and leave the L2 connection blank.