Git Tutorial

Frank Xiao

19 Aug 2025 • 4 min read

Introduction to Git

Git is a distributed version control system that tracks changes in source code during software development. It was created by Linus Torvalds in 2005 for development of the Linux kernel.

Key Concepts

Repository: A directory containing your project and its version history
Commit: A snapshot of your project at a specific point in time
Branch: A separate line of development
Remote: A copy of your repository hosted on a server (like GitHub)
Clone: A copy of a remote repository on your local machine

Getting Started

Installation

# Ubuntu/Debian
sudo apt-get install git

# CentOS/RHEL
sudo yum install git

# macOS (using Homebrew)
brew install git

Initial Configuration

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

# Set default editor
git config --global core.editor "vim"

# Check your configuration
git config --list

Creating Your First Repository

# Initialize a new repository
git init

# Or clone an existing repository
git clone <repository-url>

Basic Git Commands

Checking Status and History

# Check repository status
git status

# View commit history
git log
git log --oneline
git log --graph --oneline --all

# Show changes in working directory
git diff
git diff --staged

Making Changes

# Add files to staging area
git add <filename>
git add .                    # Add all files
git add *.txt               # Add all .txt files

# Commit changes
git commit -m "Your commit message"
git commit -am "Add and commit tracked files"

# Remove files
git rm <filename>
git rm --cached <filename>  # Remove from tracking but keep file

Undoing Changes

# Discard changes in working directory
git checkout -- <filename>
git restore <filename>      # Git 2.23+

# Unstage changes
git reset HEAD <filename>
git restore --staged <filename>  # Git 2.23+

# Amend last commit
git commit --amend

# Revert a commit
git revert <commit-hash>

Working with Branches

Branch Management

# List branches
git branch
git branch -a              # Show all branches (local + remote)

# Create a new branch
git branch <branch-name>
git checkout -b <branch-name>  # Create and switch to new branch

# Switch between branches
git checkout <branch-name>
git switch <branch-name>   # Git 2.23+

# Delete a branch
git branch -d <branch-name>
git branch -D <branch-name>  # Force delete

Merging and Rebasing

# Merge a branch into current branch
git merge <branch-name>

# Rebase current branch onto another
git rebase <branch-name>

# Resolve merge conflicts
# Edit conflicted files, then:
git add <resolved-files>
git commit

# Abort merge/rebase
git merge --abort
git rebase --abort

Remote Repositories

Working with Remotes

# Add a remote repository
git remote add origin <repository-url>

# List remotes
git remote -v

# Fetch changes from remote
git fetch origin

# Pull changes from remote
git pull origin <branch-name>
git pull --rebase origin <branch-name>

# Push changes to remote
git push origin <branch-name>
git push -u origin <branch-name>  # Set upstream

# Clone a specific branch
git clone -b <branch-name> <repository-url>

Remote Branch Management

# Create and push a new branch
git push -u origin <new-branch-name>

# Delete remote branch
git push origin --delete <branch-name>

# Track remote branch
git checkout -b <local-branch> origin/<remote-branch>

Advanced Git Operations

Stashing

# Save changes temporarily
git stash
git stash push -m "Work in progress"

# List stashes
git stash list

# Apply stash
git stash apply
git stash pop              # Apply and remove
git stash apply stash@{n}  # Apply specific stash

# Drop stash
git stash drop stash@{n}
git stash clear            # Remove all stashes

Tagging

# Create a lightweight tag
git tag <tag-name>

# Create an annotated tag
git tag -a <tag-name> -m "Tag message"

# List tags
git tag
git tag -l "v1.*"          # List tags matching pattern

# Push tags
git push origin <tag-name>
git push origin --tags     # Push all tags

# Delete tag
git tag -d <tag-name>
git push origin --delete <tag-name>

Cherry-picking and Reflog

# Apply a specific commit to current branch
git cherry-pick <commit-hash>

# View reflog (history of HEAD)
git reflog

# Reset to a previous state
git reset --hard HEAD@{n}

Git Plugin in ZSH

plugins=(
  git
  # ...
)

Alias	Full Command	Description
`g`	`git`	Main git command
`gst`	`git status`	Show the working tree status
`gaa`	`git add --all`	Add all new, modified, and deleted files to the staging area
`gcam`	`git commit --all --message`	Commit all staged changes with a message
`gp`	`git push`	Push committed changes to the remote repository
`grm`	`git rm`	Remove files from the working tree and the index
`grmc`	`git rm --cached`	Remove files from the index while keeping them in the working tree
`gco`	`git checkout`	Switch branches or restore working tree files
`gl`	`git pull`	Fetch and merge changes from the remote repository
`gcm`	`git checkout main` (or `master`)	Switch to the main branch
`ggpull`	`git pull origin "$(git_current_branch)"`	Pull changes from the remote tracking branch of the current branch