BitBucket is an awesome online service for hosting git repositories. Best part? It's FREE for teams up to 5 people! Let's walk through an example process of how simple a service such as this is, in case you aren't familiar with using git.
Say you have a project going already, and you want others to be able to pitch in. What do you do? Zip the directory and send it? NOPE! Maybe FTP into a server somewhere and upload the files for someone to download? That's even worse! What happens when you update it on your end and it's not updated on their end? How will the projects merge and lose no changes? This is the beauty of git.
Git is a version control system for code, allowing many people to work on the same 'repository' (the same bank of code. Or code project) without worrying about losing data if they work on it at the same time. I'm not going to discuss how to use git right now, but here is a great tutorial; no, right now I'll give an example of how simple it is to 'git' started!
So you have a directory you want to use git with. Great! Sign up for BitBucket then create a new repository (name your project, add contributors, etc.). Once you create this repository, you will find yourself on a page with 'starting fresh' and 'I have an existing repo'. Select 'I have an existing repo' and follow the 4 steps. You're done!
There is something called a 'hook' which, in short, allows you to setup a script of sorts on BitBucket and your development server that, when you push code changes to BitBucket, will automatically pull the changes into your live dev box, and you will see your changes right away!