What is Github ?
Github is an online platform where you can store your code for collaboration.
What is repository
A repository is simply a folder in which files of one particular project are stored.
Concept of branching on Github
Branching is a way to work on different versions of a project.
Suppose you are working on a project. Raman, your friend want to modify a part of that project. So, instead of making changes on the master project, he gets a copy of original project in which he can commit changes. If the changes he made, are approved, the admin can merge his branch into the master and hence the project is modified.
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