Rushing into the movie theater, you forgot to take a look at the seat number beforehand, under the faint light, the words on the ticket seems to hide from you. This is when Fundamental Information comes in handy. Punching seat numbers onto the tickets, the light beam goes through the paper and shows us the seat number. Even if we are sitting somewhere dark, with the help of the screen, we can still see the information we need on the ticket.
The initial idea is to find the best way that can obtain the light in the dark. by figure out different aspects of the light, we finally found that the basic element that people can see is light.