GENERATORS are used to CREATE electricity using MAGNETS and CONDUCTORS.

They do the OPPOSITE of what MOTORS do- They are rotated so that the wires experience a CHANGE IN MAGNETIC FIELD. 

This INDUCES a POTENTIAL DIFFERENCE, and if it is connected to a COMPLETE CIRCUIT it INDUCES a CURRENT too.

There are TWO types of GENERATORS:

1. ALTERNATORS

These use SLIP RINGS to generate an ALTERNATING potential difference and current.

The SLIP RINGS are used to STOP the wires from TWISTING together.

2. DYNAMOS

These use SPLIT RING COMMUTATORS to generate a DIRECT potential difference and current.

The SPLIT RING COMMUTATOR SWITCHES the CURRENT every HALF TURN to convert the ALTERNATING CURRENT into DIRECT CURRENT.