Git allows groups of people to work on the same documents (often code) at the same time, and without stepping on each other's toes. It's a distributed version control system.
Hehe, we understand.
Let us tell you a story.
Once upon a time... Alia and Matea decided that they are going to build a website. They decided that they will let people post the funny pictures of their own cats on this website, so the other people could see them and enjoy all of the catness.
They divided a project in to two parts. Alia worked on the top side of the page and Mateia on the bottom side. They needed to figure out a way of how to merge the two sides together, after they were done. They found git!
Git excepted all of the changes they made each on her own side and was kind enough to even merge it together for them. When one of them wanted to see how the other side looked like, she just preformed a git comand and git went to action, merged everything into the one big project.
OK OK, we know this is not such a good story, but we still think that now you know more about what is the primary task of git.
Of course it is a lot more powerfull than just this, but for now let this be enough.
https://try.github.io/levels/1/challenges/1