Git Basics¶

1. What is Git?¶

Git is a Distributed Version Control System (DVCS). It tracks changes to files and enables multiple people to collaborate.

Why Use Git?¶

Version Control: Save all change history of files
Backup: Store code safely
Collaboration: Multiple people can work simultaneously
Experimentation: Test new features safely

Git vs GitHub¶

Git	GitHub
Version control tool	Git repository hosting service
Works locally	Online platform
Used via command line	Provides web interface

2. Installing Git¶

macOS¶

# Install with Homebrew
brew install git

# Or install via Xcode Command Line Tools
xcode-select --install

Windows¶

Download and install from Git official website

Linux (Ubuntu/Debian)¶

sudo apt update
sudo apt install git

Verify Installation¶

git --version
# Output example: git version 2.43.0

3. Initial Git Setup¶

You need to configure your user information when using Git for the first time.

Set Username and Email¶

# Set username
git config --global user.name "John Doe"

# Set email
git config --global user.email "john@example.com"

Verify Configuration¶

# View all settings
git config --list

# Check specific settings
git config user.name
git config user.email

Set Default Editor (Optional)¶

# Set VS Code as default editor
git config --global core.editor "code --wait"

# Use Vim
git config --global core.editor "vim"

4. Creating a Git Repository¶

Method 1: Initialize a New Repository¶

# Create project folder
mkdir my-project
cd my-project

# Initialize Git repository
git init

Output:

Initialized empty Git repository in /path/to/my-project/.git/

Method 2: Clone an Existing Repository¶

# Clone repository from GitHub
git clone https://github.com/username/repository.git

5. Git's Three Areas¶

Git manages files in three areas:

┌─────────────────┐    ┌─────────────────┐    ┌─────────────────┐
│  Working        │    │  Staging        │    │  Repository     │
│  Directory      │───▶│  Area           │───▶│  (.git)         │
│  (Work space)   │    │  (Staging)      │    │  (Repository)   │
└─────────────────┘    └─────────────────┘    └─────────────────┘
      ↑                      ↑                      ↑
   Edit files            git add               git commit

Working Directory: The space where you actually modify files
Staging Area: The space where files to be committed are gathered
Repository: The space where committed snapshots are stored

Practice Examples¶

Example 1: Create Your First Repository¶

# 1. Create and navigate to practice folder
mkdir git-practice
cd git-practice

# 2. Initialize Git repository
git init

# 3. Create file
echo "# My First Git Project" > README.md

# 4. Check status
git status

Expected output:

On branch main

No commits yet

Untracked files:
  (use "git add <file>..." to include in what will be committed)
    README.md

nothing added to commit but untracked files present (use "git add" to track)

Example 2: Check Configuration¶

# View current Git configuration
git config --list --show-origin

Key Summary¶

Concept	Description
`git init`	Initialize new Git repository
`git clone`	Clone remote repository
`git config`	Modify Git configuration
Working Directory	Space for modifying files
Staging Area	Space for commit queue
Repository	Space for storing change history

Next Steps¶

Let's learn basic commands like add, commit, status, log in 02_Basic_Commands.md!