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Git Basics: Complete Beginner's Guide - Learn Git fundamentals from scratch. Commits, branches, merging, and essential Git commands for vers...
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Git Basics: Complete Beginner's Guide

Learn Git fundamentals from scratch. Commits, branches, merging, and essential Git commands for version control.

TechDevDex Team
12/15/2024
20 min
#Git#Version Control#Beginner#Fundamentals

Git Basics: Complete Beginner's Guide

Git is the most widely used version control system in the world. This comprehensive guide will teach you Git fundamentals from the ground up.

What is Git?

Git is a distributed version control system that tracks changes in files and coordinates work among multiple people. It allows you to:

  • Track changes in your code over time
  • Collaborate with other developers
  • Revert to previous versions
  • Branch and merge code safely
  • Backup your work automatically

Installing Git

Windows

bash 
# Download from https://git-scm.com/download/win
# Or use Chocolatey
choco install git

# Or use winget
winget install Git.Git

macOS

bash 
# Using Homebrew
brew install git

# Or download from https://git-scm.com/download/mac

Linux (Ubuntu/Debian)

bash 
sudo apt update
sudo apt install git

Linux (CentOS/RHEL)

bash 
sudo yum install git
# or
sudo dnf install git

First-Time Git Setup

Configure Your Identity

bash 
# Set your name
git config --global user.name "Your Name"

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

# Check your configuration
git config --list

Configure Default Editor

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

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

# Set Nano as default editor
git config --global core.editor "nano"

Creating Your First Repository

Initialize a New Repository

bash 
# Create a new directory
mkdir my-project
cd my-project

# Initialize Git repository
git init

# Check status
git status

Clone an Existing Repository

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

# Clone to specific directory
git clone https://github.com/username/repository.git my-folder

# Clone with specific branch
git clone -b branch-name https://github.com/username/repository.git

Basic Git Workflow

1. Check Status

bash 
# See current status
git status

# Short status
git status -s

2. Add Files to Staging

bash 
# Add specific file
git add filename.txt

# Add all files
git add .

# Add files by pattern
git add *.js

# Interactive add
git add -i

3. Commit Changes

bash 
# Commit with message
git commit -m "Add initial project files"

# Commit with detailed message
git commit -m "Add user authentication

- Implement login functionality
- Add password validation
- Create user session management"

# Amend last commit
git commit --amend -m "Updated commit message"

4. View History

bash 
# View commit history
git log

# One-line format
git log --oneline

# Graph format
git log --graph --oneline --all

# Show changes
git log -p

Working with Branches

Create and Switch Branches

bash 
# Create new branch
git branch feature-branch

# Switch to branch
git checkout feature-branch

# Create and switch in one command
git checkout -b feature-branch

# Modern way (Git 2.23+)
git switch -c feature-branch

List and Delete Branches

bash 
# List local branches
git branch

# List all branches (including remote)
git branch -a

# Delete local branch
git branch -d feature-branch

# Force delete branch
git branch -D feature-branch

# Delete remote branch
git push origin --delete feature-branch

Merge Branches

bash 
# Switch to main branch
git checkout main

# Merge feature branch
git merge feature-branch

# Merge with no fast-forward
git merge --no-ff feature-branch

# Squash merge
git merge --squash feature-branch

Remote Repositories

Add Remote

bash 
# Add remote repository
git remote add origin https://github.com/username/repository.git

# List remotes
git remote -v

# Change remote URL
git remote set-url origin https://github.com/username/new-repository.git

Push and Pull

bash 
# Push to remote
git push origin main

# Push new branch
git push -u origin feature-branch

# Pull changes
git pull origin main

# Fetch without merging
git fetch origin

Essential Git Commands

Viewing Changes

bash 
# Show differences
git diff

# Show staged differences
git diff --staged

# Show commit differences
git diff HEAD~1

# Show file history
git log --follow filename.txt

Undoing Changes

bash 
# Unstage file
git reset HEAD filename.txt

# Discard changes
git checkout -- filename.txt

# Reset to last commit
git reset --hard HEAD

# Reset to specific commit
git reset --hard commit-hash

Stashing

bash 
# Stash current changes
git stash

# Stash with message
git stash push -m "Work in progress"

# List stashes
git stash list

# Apply stash
git stash apply

# Apply and remove stash
git stash pop

# Drop stash
git stash drop

Best Practices

Commit Messages

bash 
# Good commit messages
git commit -m "Add user authentication feature"
git commit -m "Fix bug in login validation"
git commit -m "Update documentation for API endpoints"

# Bad commit messages
git commit -m "fix"
git commit -m "update"
git commit -m "changes"

.gitignore File

Create a .gitignore file to exclude files:

text 
# Dependencies
node_modules/
package-lock.json

# Build outputs
dist/
build/
*.exe

# Environment files
.env
.env.local

# IDE files
.vscode/
.idea/
*.swp

# OS files
.DS_Store
Thumbs.db

Branch Naming

bash 
# Good branch names
feature/user-authentication
bugfix/login-validation
hotfix/security-patch
release/v1.2.0

# Bad branch names
new-feature
fix
test

Common Git Scenarios

Scenario 1: Undo Last Commit

bash 
# Keep changes, unstage
git reset --soft HEAD~1

# Discard changes completely
git reset --hard HEAD~1

Scenario 2: Change Last Commit

bash 
# Add more changes
git add .
git commit --amend -m "Updated commit message"

Scenario 3: Merge Conflicts

bash 
# When merge conflict occurs
git status
# Edit conflicted files
git add resolved-file.txt
git commit

Scenario 4: Rebase Instead of Merge

bash 
# Rebase feature branch onto main
git checkout feature-branch
git rebase main

# Interactive rebase
git rebase -i HEAD~3

Advanced Git Features

Aliases

bash 
# Create useful aliases
git config --global alias.st status
git config --global alias.co checkout
git config --global alias.br branch
git config --global alias.ci commit
git config --global alias.unstage 'reset HEAD --'
git config --global alias.last 'log -1 HEAD'
git config --global alias.visual '!gitk'

Hooks

bash 
# Pre-commit hook example
#!/bin/sh
# Run tests before commit
npm test

Submodules

bash 
# Add submodule
git submodule add https://github.com/user/repo.git path/to/submodule

# Update submodules
git submodule update --init --recursive

Troubleshooting

Common Issues

  1. "Your branch is ahead of origin/main"

    bash 
    git push origin main

  2. "Your branch and origin/main have diverged"

    bash 
    git pull --rebase origin main

  3. "Please tell me who you are"

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

  4. Accidentally committed to wrong branch

    bash 
    git checkout correct-branch
git cherry-pick commit-hash
git checkout wrong-branch
git reset --hard HEAD~1

Git GUI Tools

Command Line Tools

  • Git Bash (Windows)
  • Terminal (macOS/Linux)

GUI Applications

  • GitHub Desktop
  • Sourcetree
  • GitKraken
  • VS Code Git Integration

Conclusion

Git is an essential tool for any developer. By mastering these fundamentals, you'll be able to:

  • Track your code changes effectively
  • Collaborate with other developers
  • Maintain clean project history
  • Handle complex development workflows

Remember to:

  • Commit often with meaningful messages
  • Use branches for feature development
  • Keep your repository clean
  • Learn advanced features gradually
  • Practice regularly

Happy coding! 🚀