The collaboration layer GitHub adds on top of Git — repositories and their settings, issues, pull requests, and code review — and where the line between the version control engine and the platform actually falls.
5 topics
Everything so far has been Git, which runs entirely on your machine with no server. This chapter is about GitHub, the hosting and collaboration layer built on top of it. Keeping the two straight is the first thing to get right: Git gives you commits, branches, and history; GitHub adds the server, the web UI, permissions, and the pull-request workflow that none of Git's own commands know about.
The five topics build in order. What GitHub is sets the boundary between engine and platform, repositories cover the settings that quietly govern behavior, and issues, pull requests, and code review are the primitives a team actually works through — the unit of change, the conversation around it, and the gate that decides whether it merges.