The project to be considered Open Source it must have a license!

There are 10 criterias that the license has to meet. Check online at opensource.org. You can find licenses on the site.

He likes the MIT license and uses this one.

###Code of Conduct

Not technically required but important. He never had to enforce it on anyone, but you can point people to it when they are not nice.

###Readme

We will talk about it later...