What GitHub Is (and What It Is Not)

Most people meet GitHub before they meet Git, which is roughly like learning about libraries before learning to read. This page puts them back in order.

GitHub is a company that stores copies of Git repositories on the internet and builds a website around them. That is it. It is not a different version of Git, not a replacement for it, and not required to use it.

The storage half

A copy of your repository lives on GitHub's servers. Your machine can send commits to it and fetch commits from it, and both copies hold the same history.

That copy is called a remote: a repository somewhere else that yours knows about. The word is worth learning properly, because it is what the next three topics are all about. A remote is not a backup service and not a master copy — it is another repository, which happens to be somewhere you can reach.

The website half

Everything else GitHub offers — issues, pull requests, code review, project boards, releases — is GitHub's own invention, built on top of the storage.

Git has no idea what a pull request is. That is not a criticism of either one; it is the reason those features have different names on different hosts, and the reason your Git knowledge transfers between them unchanged while your GitHub knowledge only mostly does.

Why anyone bothers

Three reasons, in order of how soon you will feel them.

A copy that survives your laptop. Chapter 1 was blunt about this: until now, Sandpiper's entire history has been one hard disk away from not existing.

A way for someone else to get the project. Theo cannot clone a folder on your desk.

And a place where a change can be discussed before it is accepted. That third one is what Chapter 8 is about, and it is the reason teams pick a host rather than a bare server somewhere.

The alternatives, once

GitLab, Bitbucket, Codeberg, and a self-hosted server in a company's own data centre all do the same job, and all speak exactly the same Git. Your first employer may well use one of them.

What transfers completely is everything in Chapters 1 to 6, plus push, pull and clone. What does not transfer is where the buttons are. This book describes GitHub's features by what they do rather than by where they sit on the page, because button positions are the fastest-rotting sentences in any course like this one.

What "public" means

A repository on GitHub is either private, visible only to you and people you invite, or public, readable by anyone at all.

Public means the whole thing: every file, every commit, every message, and your name and email on all of them. Not just the current state — the history, including anything you committed and later removed. Chapter 5 made that point about secrets; Chapter 9 comes back to it properly, before Sandpiper goes public.