Stage and Commit

You have a file. Now you will move it through the three areas — staging it, then committing it — and build a real commit history.

Stage the File

git add README.md

Run git status again:

On branch main

No commits yet

Changes to be committed:
  (use "git rm --cached <file>..." to unstage)
	new file:   README.md

README.md moved from Untracked files to Changes to be committed. It is now in the Staging Area, ready to go into the next commit.

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Commit

git commit -m "Initial commit"

Output:

[main (root-commit) a1b2c3d] Initial commit
 1 file changed, 1 insertion(+)
 create mode 100644 README.md

Git saved a permanent snapshot. The hash a1b2c3d is a unique fingerprint for this commit — every commit gets one.

A good commit message:

• Uses the imperative mood: "Add README" not "Added README"
• Describes the change, not the file: "Add project overview" not "Edit README.md"
• Is short enough to read in a one-line log (50 chars or less)

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View Your History

git log

Output:

commit a1b2c3d4e5f6... (HEAD -> main)
Author: Your Name <you@example.com>
Date:   Fri Jan 10 10:00:00 2025

    Initial commit

HEAD -> main tells you:

• main is the current branch
• HEAD is pointing at the latest commit on that branch

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Make a Second Commit

Add some content to the README:

echo "A practice repository for learning Git." >> README.md

Now run through the full cycle:

git status        # see the modified file
git add README.md # stage it
git commit -m "Add project description to README"
git log           # see both commits

Your log now shows two commits. The most recent is at the top.

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What Happens Inside .git/

You do not need to understand the internals, but this mental model helps:

Each commit stores:

1. A snapshot of every tracked file at that moment
2. A pointer to the parent commit (except the first)
3. Your name, email, and a timestamp
4. Your commit message

Git does not store diffs — it stores full snapshots. The diff you see in git diff is computed on the fly by comparing two snapshots.

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Summary

Command	What it does
git add <file>	Move changes from Working Directory to Staging Area
git add .	Stage all changes in the current directory
git commit -m "..."	Snapshot everything in Staging Area into the repo
git log	Show the commit history