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The repository has one "master" branch, which is what we release to customers. It also has a "staging" branch, where all new code is stored for testing prior to being merged into "master". Each contributor creates their own development branch, branched from master, and commits their code there; then, regularly "pushes" the commits up to the remote server for backup.
When all the code is ready, the contributor creates a pull request in order to merge their changes from the development private branch into the "staging" branch. Instructions on how to do all of this followshared develop branch.

What are GIT, GitHub, Sourcetree, and Bitbucket?

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