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There's a Nature blog posting with more detail on how git can help,
How do I use GitHub?
A few basic pointers with illustration are available on my GitHub Illustrated page. In addition, other Other people have produced tutorials on on Version Control, Basics of using Git, and and workflow using Git. I'm not aware of a tutorial of social scientists. If you find one, please please let me know.
Differences between GitHub.com and The University of Texas’s repository (github.austin.utexas.edu)
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