What actually Github is , well according to wikipedia:-
GitHub is a web-based Git or version control repository and Internet hosting service. It offers all of the distributed version control and source code management (SCM) functionality of Git as well as adding its own features. It provides access control and several collaboration features such as bug tracking, feature requests, task management, and wikis for every project.
GitHub offers both plans for private and free repositories on the same account which are commonly used to host open-source software projects.
To understand GitHub, you must first have an understanding of Git. Git is an open-source version control system that was started by Linus Trovalds(Creator of Linux).
Git is easy to learn and has a tiny footprint with lightning fast performance. It outclasses SCM tools like Subversion, CVS, Perforce, and Clear Case with features like cheap local branching, convenient staging areas, and multiple workflows.
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