Wikipedia is the world's biggest encyclopedia. If just the English version of Wikipedia was printed, without pictures, it would be almost 3000 volumes. You can see what that looks like visually by clicking here.
Have you ever wanted to try contributing to Wikipedia? Anyone can write articles in Wikipedia, but there are a few rules to follow, and you need to know how to format your articles as well. For this reason, Wikipedia has created several ways for people to learn how to contribute. You can try the Wikipedia Adventure Game or you can start at the “Joining Wikipedia” page.