Spark image

A simple switch
This can either be open (a) or closed (b). If the switch is open the current can't flow and the bulb is off (A). If the switch is closed current can flow round the circuit and the bulb lights up (B).

Two way switch
The next switch can change the path of the current. It has two contacts (c and d). It is called a TWO-WAY switch. When the switch is in position c, bulb C lights. When the switch is moved to position d bulb D lights.

© Keith Gibbs 2009