Seeing what changed

Git is far less mysterious once you can see what it's doing. Three read-only commands tell you everything about the state of your repository — and you should reach for them constantly, especially before committing or running anything destructive.

git status — the most important command

git status answers "where am I, and what's changed?" It lists which files are modified, which are staged for the next commit, and which are untracked (new files git isn't watching yet):

git status

Run it often. Before every commit, git status tells you exactly what you're about to record — no surprises.

git diff — the exact changes

status tells you which files changed; git diff shows you what changed, line by line:

git diff            # changes in your working tree, not yet staged
git diff --staged   # changes you've staged, about to be committed

Lines starting with + are additions, - are removals. Reading the diff before you commit is the single best habit for catching mistakes — a stray debug line, a wrong value, a file you didn't mean to touch.

git log — the history

git log walks back through your commits, newest first:

git log                  # full history with messages
git log --oneline        # one compact line per commit
git log --oneline -5     # just the last five

Each commit has a unique hash (like a1b2c3d); you'll use those short hashes to refer to specific commits later (when undoing, comparing, or bisecting).

Reviewing AI-generated changes

This is also exactly how you review a change an agent made: git status to see what it touched, git diff to read every line it wrote, before you commit. Never commit a diff you haven't read — whoever wrote it.

Where to go next

You can inspect any state of your repo. Next: branching and switching — working on changes in isolation without disturbing your main line.