This is how we, Mozilla, define what we do in our Manifesto:
We create communities of people involved in making the Internet experience better for all of us.
What’s interesting here is that — in this sentence — we don’t mention Firefox at all. The goal is to make the Internet better for all of us, and that’s why we make Firefox (along with the very promising Firefox OS project). But a big piece of what we do, even if it’s not very visible from the outside, is to create communities of people. These people — that we call Mozillians–, in turn, build the products that make the Internet better. What makes makes Mozillians — most of them are volunteers — contribute to Mozilla?
French-speaking communities in MozCamp EU in Warsaw, cc by Flore