Git 101 — Guide & Interactive Lab

Reference covers setup, auth, branching, rebase, stashing and undo; the lab is a simplified single-file simulator.

What Git and GitHub are

Git tracks versions of your project on your machine.
GitHub hosts Git repositories online for collaboration.

Prerequisites & identity Expand

Install Git from git-scm.com/downloads. Create a GitHub account at github.com.

git config --global user.name "Your Name"
git config --global user.email "your.email@example.com"

Authentication (PAT, SSH, CLI, credential manager)

GitHub does not accept account passwords for Git over HTTPS. Use a Personal Access Token, SSH keys, GitHub CLI (gh auth login), or the OS Git Credential Manager.

See the full guide for token scopes, ssh-keygen -t ed25519, and testing with ssh -T git@github.com.

Happy path (clone, daily cycle)

git init
git remote add origin https://github.com/USER/REPO.git

# OR
git clone https://github.com/USER/REPO.git

git add .
git commit -m "Your message"
git push origin main
git pull

Branching & merge

git checkout -b feature-login
# ... commits ...
git checkout main
git pull origin main
git merge feature-login
git push origin main

Merge vs rebase

Merge preserves full history; adds a merge commit.

Rebase replays your commits on top of main for a linear history — avoid on shared branches you do not own.

git checkout feature-branch
git pull origin main --rebase

Fetch vs pull & safe update

git pull fetches and merges. git fetch only downloads — inspect before merging.

git fetch origin
git log main..origin/main
git merge origin/main

Quick check (interactive)

Flip each card — term on the front, answer on the back.

Cheat sheet

Command	Description
git status	Check file status
git log --oneline --graph	Visual commit history
git diff	Unstaged changes
git branch -a	List local and remote branches
git remote -v	Show remote URLs
git commit --amend	Fix the last commit message
git pull --rebase	Pull with rebase

Command Center

1. Standard Workflow

2. Shelf Work (Stash)

3. Undo Mistakes

4. Branching

$ status

Working tree clean. Edit a file to start.

Next: Use (edit files) to create a change.

Switched to new branch 'feature'

Working
Dir

Staging
Index

Local
Repo

Remote
Repo

Stash