Switches are simple Electronic devices which simply allow you to either turn a circuit on or off or switch between different desired functions. A few examples of common switch types which you may use are shown in Fig 1.
The points of a switch are commonly referred to as ‘Poles’. On circuit symbols for switches the poles are often shown as small circles.
If you look carefully at Fig 2 you can work out the type of switch by looking at the poles. The throw means the arm of the switch which is moving to make contact.
There are literally hundreds of different types and combinations of switches (which you may wish to research) but some of the more common ones associated with some of the activities in this booklet are shown here.
Push to Make (PTM) Switches will allow a circuit to work when pressed. A Push to Break (PTB) switch will stop a circuit working when pressed.