A camera is a way of getting part of the world around us onto something that we can keep. The first cameras did this by putting a lens in a large dark box (camera means room in Latin). The lens made the light coming from the world outside the box come together and so make a smaller image. At the back of the box they placed a sheet of glass with chemicals on that changed from colourless to black when light fell on them. They then found a way of making those black areas permanent, and then they found a way of printing the images so that what was black on the glass became white on the print.

After this all the changes were to make cameras smaller and to be able to use a roll of film and to capture the world in colour and as a movie.

Although film cameras are still about, the way of keeping the images has changed in most cameras. Now the light usually falls on a small chip that turns the light it received into digital information. That can be stored, sent around the world and changed how we want it. And it can still be used to print photographs.