GitHub is a company that hosts git repositories online and provides several collaboration features. GitHub fosters a great user community and has built a nice graphical interface to git, adding great visualization capacities of your data and codes. You can access their service through their main website. GitHub has also created an enterprise version of their system to allow companies and institutions to deploy their own instance, provide more control on how you organize your data and collaborate. NCEAS is running its own GitHub instance.
See this page to get started with git
Everybody can create an account on GitHub.com and use public repositories to foster collaborative code development. Note that by default all the repositories are public, so think wisely before adding any sensitive data to your repository. Note that we generally recommend to use git to manage your codes and not your data.
NCEAS has its own GitHub instance. You can use this instance to collaborate with your working group participants and set up as many private repositories as you would like to.
We generally recommend to use GitHub.com. You might want to consider NCEAS instance if:
You are working with sensitive data or your working group participants are worried about sharing some of the data used in your analysis
You are exceeding the size limit of free GitHub.com
You want a private repo for other reasons
Note this is not a definitive choice as it is quite easy to switch from one instance to the other.