Reflection, Refraction and Diffraction

Even though light often looks white, it is made up of lots of different colours all added together. 

When we talk about light we usually mean the light we can see with our eyes. This is also called visible or optical light.

One of the first people to study light was Ibn al-Haytham (known as Alhazen). He was a Muslim, living in Egypt in the early 11th Century. Alhazen is first person we know of who used the scientific method. He wanted to know why our eyes could see things.