*Mentor: [https://mozillians.org/en-US/u/Gijs/ Gijs Kruitbosch]
*Participant: [https://mozillians.org/en-US/u/Rakhi/ Rakhi Sharma]
* [http://rakhisharmarakhish.githubwordpress.io/Verbose-Journalcom/ Participant Blog]
Firefox for desktop is used by hundreds of millions of people every day. We control what it looks like using CSS, XUL (a markup language that's a bit like HTML), and JavaScript. There's also a small amount of C++ here and there.