2.2 Install check and first vocabulary
Before commands, confirm Git exists.
git --version
What you see: a version line such as git version 2.x.x. If the command is not found, install Git for your OS from the official Git site, or use GitHub Codespaces where Git is already present.
| Word | Meaning |
|---|---|
| Repository (repo) | The project folder tracked by Git (includes a hidden .git directory) |
| Working tree | The files you edit normally in the folder |
| Staging area (index) | The waiting room — files listed for the next commit |
| Commit | A saved snapshot with message, author and parent link |
| Hash (SHA) | Long id for a commit, e.g. a3f2c1… (you often use the short form) |
working tree staging area commit history
(you edit files) ---> (git add) -----------> (git commit)
^ |
| |
+------------- git restore / checkout <------+