Module 04 of 10 · log · diff · show

Viewing History

git log — Browse Your Commits

Once you have commits, you can view them all:

git log

Each entry shows the commit hash (a unique ID), author, date, and message. Press q to quit the pager in a real terminal.

Compact View

For a cleaner one-line summary:

git log --oneline

This is the format most developers use day-to-day — easier to scan a long history.

git diff — See What Changed

git diff shows the difference between your current working files and the last commit:

git diff

Lines starting with + are additions (green), lines starting with - are removals (red).

Staged Changes

To see what's staged (already in the next commit):

git diff --staged
Tip: Run git diff before staging and git diff --staged after staging. This lets you double-check your changes before committing.

git show — Inspect a Single Commit

To see exactly what a specific commit changed:

git show             # shows the most recent commit
git show a1b2c3d     # shows a specific commit by its short hash

The hash comes from git log --oneline. You only need the first 7 characters.

Reading a Diff

diff --git a/README.md b/README.md
--- a/README.md
+++ b/README.md
@@ -1,3 +1,4 @@
 # My Project
-This is version 1.
+This is version 2.
+Added a new line.

The @@ line tells you where in the file the change is. Lines with no prefix are context (unchanged).

Your Challenges

Run git log to view the commit history
Run git log --oneline for the compact view
Edit a file (echo change > file.txt), then run git diff
Run git show to inspect the most recent commit
Module 4 complete! You can now navigate your project's history and inspect any change. These skills are invaluable for debugging.
student@git-mastery: ~/my-project