Inspect Changes

Edit. Status. Add. Commit. Push. That loop is 80% of daily Git work. Before committing, you should always know exactly what you are about to save.

See Unstaged Changes

git diff

git diff compares your Working Directory to the Staging Area. It shows changes you have made but not yet staged.

Example — you added a line to README.md:

diff --git a/README.md b/README.md
index 1234567..abcdefg 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,3 @@
 # My First Repo
 A practice repository for learning Git.
+Added a new line.

Reading the diff:

• Lines starting with + are additions (shown in green in most terminals)
• Lines starting with - are deletions (shown in red)
• Lines with no prefix are unchanged context lines

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See Staged Changes

git diff --staged

This compares the Staging Area to the last commit — it shows exactly what will be saved when you run git commit. Always review this before committing.

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Stage Everything vs. Selectively

Stage all changes in the current directory

git add .

Convenient, but be careful. It stages every modified and untracked file, including things you may not want committed (secrets, large files, debug code).

Stage specific files

git add README.md notes.txt

More deliberate. Each commit should represent one logical change, not "everything I happened to touch."

A good habit: run git status after git add . to confirm nothing unexpected was staged.

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A Readable Log

The default git log is verbose. For a quick overview:

git log --oneline

Output:

a1b2c3d (HEAD -> main, origin/main) Add note from lesson 2.6
9f8e7c6 Add project description to README
3d2c1b0 Initial commit

Each line: <hash> <message>. The parenthetical shows which branches and remotes point to each commit.

See a graph of branches

git log --oneline --graph --all

This becomes useful once you have multiple branches.

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Practice: The Full Loop

Run through this three times. Each time, make a small meaningful change:

# 1. Edit a file
echo "Practice run 1" >> README.md

# 2. Check what changed
git status
git diff

# 3. Stage
git add README.md

# 4. Verify what is staged
git diff --staged

# 5. Commit
git commit -m "Add practice run 1 note"

# 6. Push
git push

# 7. Confirm on GitHub

After three rounds you will have the muscle memory. This loop is what you do dozens of times a day.

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Summary

Command	What it shows
git diff	Working Directory vs. Staging Area
git diff --staged	Staging Area vs. last commit
git add .	Stage everything (use carefully)
git add <file>	Stage a specific file
git log --oneline	Compact one-line history
git log --oneline --graph --all	History with branch graph