Git 103: diff, add, commit, logGit 103: diff, add, commit, log

A commit should not be a blind save.

Before committing, inspect what changed.

See the exact change

Edit README.md:

# Git 10x Practice

This repository is for learning safe Git habits.

Then run:

git status
git diff

git diff shows unstaged changes.

You will see removed lines with - and added lines with +.

Read the diff before asking Git to save anything.

Stage the files

Staging means choosing what belongs in the next commit.

git add README.md .gitignore

Then check again:

git status

The files should now be staged.

If you want to inspect staged changes:

git diff --staged

Make the first commit

Commit with a clear message:

git commit -m "docs: add practice README"

A useful commit message says what changed and why it matters.

Weak:

update

Better:

docs: add setup notes for Git practice repo

The better message is searchable and reviewable.

Read history

Run:

git log --oneline

You should see your commit with a short hash and message.

That hash is a stable pointer to a saved point in history.

The safest daily loop

Use this loop whenever you or an AI assistant changes files:

git status
git diff
git add <files>
git diff --staged
git commit -m "type: message"
git log --oneline -5

The important part is the inspection before commit.

Do not use git add . blindly

git add . stages many changes at once.

It is useful when you already inspected the whole diff. It is risky when you have not.

Before git add ., ask:

• did I check git status?
• did I read git diff?
• are there generated files?
• are there secrets?
• are there unrelated changes from another task?

When in doubt, add specific files.

Practice: write one commit carefully

Add this section to README.md:

## Commands I know

- git status
- git diff
- git add
- git commit

Then run:

git status
git diff
git add README.md
git diff --staged
git commit -m "docs: list first Git commands"
git log --oneline -3

Checkpoint:

• git status should be clean after the commit.
• git log --oneline should show two commits.

Next: Git 104 - branches let you experiment safely.