Types;

1 . converging beam:they are produced from a large source and meet at a point forming convergent beam. It does not require a device.  Example includes sunlight. 

2. Diverging beam:they are produced from a small source and are scattered,  that is they emerge from a source and diffuse in different directions. It requires a device. Example includes torchlight. 

3.parallel beam:these are rays of light produced in a straight line. Example includes ray box.