Git & GitHub for Beginners: Commands, SSH, Private vs Public Repos & Workflow

Git is the most popular version control system that tracks changes in your code, while GitHub is a cloud platform for hosting Git repositories. Together, they’re essential tools for every developer, enabling collaboration, backup, and project management.

In this comprehensive guide, you’ll learn:

• What Git and GitHub are and why they matter
• Essential Git commands and workflows
• Private vs Public repositories
• SSH setup and authentication
• Cloning, branching, and collaboration
• Best practices and real-world examples
• Free learning resources

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What Are Git and GitHub?

Git (Version Control System)

Git tracks changes in your files over time, allowing you to:

• Save snapshots of your project (commits)
• Revert to previous versions
• Work on different features simultaneously (branches)
• Collaborate with others without conflicts

GitHub (Cloud Platform)

GitHub hosts your Git repositories online, providing:

• Remote backup of your code
• Collaboration tools (pull requests, issues)
• Project management features
• Portfolio showcase for developers

# Think of it this way:
# Git = Local version control on your computer
# GitHub = Online storage + collaboration platform

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Installing Git

Windows

# Download from: https://git-scm.com/download/win
# Or use package manager
winget install Git.Git

macOS

# Using Homebrew
brew install git

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

Linux (Ubuntu/Debian)

sudo apt update
sudo apt install git

Verify Installation:

git --version
# Output: git version 2.42.0

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Initial Git Setup

Configure your identity (required for commits):

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

# Set default branch name
git config --global init.defaultBranch main

# Check your configuration
git config --list

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Essential Git Commands

1. Repository Initialization

# Create a new Git repository
git init

# Check repository status
git status

# Example output:
# On branch main
# No commits yet
# nothing to commit (create/copy files and use "git add" to track)

2. Staging and Committing

# Add files to staging area
git add filename.txt          # Add specific file
git add .                     # Add all files
git add *.js                  # Add all JavaScript files

# Check what's staged
git status

# Commit changes
git commit -m "Add initial project files"

# Add and commit in one step
git commit -am "Update existing files"

3. Viewing History

# View commit history
git log

# Compact view
git log --oneline

# View changes
git diff                      # Unstaged changes
git diff --staged            # Staged changes
git diff HEAD~1              # Compare with previous commit

4. Branching

# List branches
git branch

# Create new branch
git branch feature-login

# Switch to branch
git checkout feature-login

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

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

# Delete branch
git branch -d feature-login

5. Merging

# Switch to main branch
git checkout main

# Merge feature branch
git merge feature-login

# Delete merged branch
git branch -d feature-login

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Remote Repositories (GitHub)

Connecting to GitHub

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

# View remotes
git remote -v

# Push to GitHub
git push -u origin main      # First time
git push                     # Subsequent pushes

# Pull from GitHub
git pull origin main

Cloning Repositories

# Clone with HTTPS
git clone https://github.com/username/repository.git

# Clone with SSH (after SSH setup)
git clone git@github.com:username/repository.git

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

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

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Private vs Public Repositories

Public Repositories

Characteristics:

• ✅ Visible to everyone on the internet
• ✅ Anyone can view and clone
• ✅ Great for open-source projects
• ✅ Free on GitHub
• ✅ Good for portfolio/showcase

Example Use Cases:

# Portfolio website
git clone https://github.com/username/portfolio.git

# Open source library
git clone https://github.com/facebook/react.git

# Learning projects
git clone https://github.com/username/javascript-projects.git

Private Repositories

Characteristics:

• 🔒 Only visible to you and collaborators
• 🔒 Requires authentication to access
• 🔒 Perfect for commercial projects
• 🔒 Free on GitHub (with limits)
• 🔒 Secure for sensitive code

Example Use Cases:

# Company project (requires authentication)
git clone https://github.com/company/secret-project.git

# Personal projects with sensitive data
git clone git@github.com:username/private-app.git

# Client work
git clone https://github.com/username/client-website.git

Comparison Table

Feature	Public Repository	Private Repository
Visibility	Everyone	Invited users only
Cost	Free	Free (limited)
Cloning	Anyone	Authenticated users
Search	Appears in search	Hidden
Forks	Anyone can fork	Collaborators only
Issues	Public discussions	Private discussions
Best For	Open source, portfolios	Commercial, sensitive

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SSH Setup for GitHub

SSH provides secure, password-free authentication with GitHub.

1. Generate SSH Key

# Generate new SSH key
ssh-keygen -t ed25519 -C "your.email@example.com"

# For older systems
ssh-keygen -t rsa -b 4096 -C "your.email@example.com"

# Press Enter to accept default location
# Enter passphrase (optional but recommended)

2. Add SSH Key to SSH Agent

# Start SSH agent
eval "$(ssh-agent -s)"

# Add SSH key to agent
ssh-add ~/.ssh/id_ed25519

# On macOS, add to keychain
ssh-add --apple-use-keychain ~/.ssh/id_ed25519

3. Add SSH Key to GitHub

# Copy public key to clipboard
# On macOS
pbcopy < ~/.ssh/id_ed25519.pub

# On Linux
cat ~/.ssh/id_ed25519.pub | xclip -selection clipboard

# On Windows
clip < ~/.ssh/id_ed25519.pub

Then on GitHub:

1. Go to Settings → SSH and GPG keys
2. Click “New SSH key”
3. Paste your public key
4. Give it a descriptive title

4. Test SSH Connection

# Test connection
ssh -T git@github.com

# Expected output:
# Hi username! You've successfully authenticated, but GitHub does not provide shell access.

5. Use SSH URLs

# Clone with SSH
git clone git@github.com:username/repository.git

# Change existing repo to SSH
git remote set-url origin git@github.com:username/repository.git

# Clone with specific SSH key (useful when you have multiple keys)
GIT_SSH_COMMAND='ssh -i ~/.ssh/id_rsa_[SPECIFIC]' git clone git@github.com:username/repo.git

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Complete Git Workflow Examples

Starting a New Project

# 1. Create project folder
mkdir my-awesome-project
cd my-awesome-project

# 2. Initialize Git
git init

# 3. Create initial files
echo "# My Awesome Project" > README.md
echo "console.log('Hello World!');" > app.js

# 4. Add and commit
git add .
git commit -m "Initial commit: Add README and app.js"

# 5. Create GitHub repository (on GitHub.com)
# Then connect local repo to GitHub
git remote add origin git@github.com:username/my-awesome-project.git
git push -u origin main

Working with Existing Project

# 1. Clone repository
git clone git@github.com:username/existing-project.git
cd existing-project

# 2. Create feature branch
git checkout -b feature/user-authentication

# 3. Make changes
echo "// User login functionality" >> auth.js

# 4. Stage and commit
git add auth.js
git commit -m "Add user authentication module"

# 5. Push feature branch
git push -u origin feature/user-authentication

# 6. Create Pull Request on GitHub
# 7. After review, merge and cleanup
git checkout main
git pull origin main
git branch -d feature/user-authentication

Collaborative Workflow

# 1. Always start with latest code
git checkout main
git pull origin main

# 2. Create feature branch
git checkout -b feature/shopping-cart

# 3. Work on feature
# ... make changes ...
git add .
git commit -m "Implement shopping cart functionality"

# 4. Push and create PR
git push -u origin feature/shopping-cart
# Create Pull Request on GitHub

# 5. Handle feedback
# ... make more changes ...
git add .
git commit -m "Address PR feedback: improve error handling"
git push

# 6. After merge, cleanup
git checkout main
git pull origin main
git branch -d feature/shopping-cart
git push origin --delete feature/shopping-cart

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Advanced Git Commands

Undoing Changes

# Unstage files
git reset filename.txt

# Discard working directory changes
git checkout -- filename.txt

# Undo last commit (keep changes)
git reset --soft HEAD~1

# Undo last commit (discard changes)
git reset --hard HEAD~1

# Revert a commit (safe for shared repos)
git revert HEAD

Stashing Changes

# Save work in progress
git stash

# List stashes
git stash list

# Apply latest stash
git stash pop

# Apply specific stash
git stash apply stash@{0}

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

Viewing and Comparing

# Show commit details
git show HEAD
git show abc123

# Compare branches
git diff main..feature-branch

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

# Show who changed what
git blame filename.txt

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GitHub Features

Issues and Project Management

# Reference issues in commits
git commit -m "Fix login bug (closes #15)"

# Link to issues
git commit -m "Implement user profile (ref #23)"

Pull Requests

Creating Pull Requests:

1. Push feature branch to GitHub
2. Go to repository on GitHub
3. Click “Compare & pull request”
4. Add description and reviewers
5. Create pull request

Pull Request Best Practices:

• Write clear titles and descriptions
• Reference related issues
• Add screenshots for UI changes
• Request specific reviewers
• Keep PRs small and focused

GitHub Actions (CI/CD)

# .github/workflows/ci.yml
name: CI
on: [push, pull_request]
jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v3
      - uses: actions/setup-node@v3
        with:
          node-version: '18'
      - run: npm install
      - run: npm test

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Common Git Scenarios

Merge Conflicts

# When merge conflicts occur
git merge feature-branch
# Auto-merging index.html
# CONFLICT (content): Merge conflict in index.html

# Edit conflicted files, look for:
<<<<<<< HEAD
Current branch content
=======
Feature branch content
>>>>>>> feature-branch

# After resolving conflicts
git add .
git commit -m "Resolve merge conflicts"

Working with Forks

# Fork repository on GitHub, then clone your fork
git clone git@github.com:yourusername/forked-repo.git
cd forked-repo

# Add original repository as upstream
git remote add upstream git@github.com:original-owner/original-repo.git

# Keep your fork updated
git fetch upstream
git checkout main
git merge upstream/main
git push origin main

Large Files with Git LFS

# Install Git LFS
git lfs install

# Track large files
git lfs track "*.psd"
git lfs track "*.zip"

# Add .gitattributes
git add .gitattributes

# Normal git workflow
git add large-file.psd
git commit -m "Add design files"
git push

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Git Best Practices

Commit Messages

# Good commit messages
git commit -m "Add user authentication system"
git commit -m "Fix: Resolve login redirect issue"
git commit -m "Update: Improve error handling in API calls"

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

Branching Strategy

# Feature branches
git checkout -b feature/user-profile
git checkout -b feature/payment-integration

# Bug fixes
git checkout -b bugfix/login-error
git checkout -b hotfix/security-patch

# Releases
git checkout -b release/v1.2.0

.gitignore File

# Create .gitignore file
cat > .gitignore << EOF
# Dependencies
node_modules/
vendor/

# Environment files
.env
.env.local

# Build outputs
dist/
build/
*.log

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

# OS files
.DS_Store
Thumbs.db
EOF

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Free Git & GitHub Learning Resources

Interactive Tutorials

• 🔗 GitHub Skills – Interactive GitHub courses
• 🔗 Learn Git Branching – Visual Git tutorial
• 🔗 Git Immersion – Hands-on Git workshop
• 🔗 Atlassian Git Tutorials – Comprehensive guides

Documentation & References

• 📚 Pro Git Book – Free official Git book
• 📚 GitHub Docs – Official GitHub documentation
• 📚 Git Reference – Command reference

Video Courses

• 🎥 Git & GitHub Crash Course – Traversy Media
• 🎥 Git Tutorial for Beginners – Programming with Mosh
• 🎥 GitHub for Beginners – freeCodeCamp

Practice Platforms

• 💻 GitHub – Create free account and practice
• 💻 GitLab – Alternative platform with CI/CD
• 💻 Bitbucket – Atlassian’s Git platform

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Troubleshooting Common Issues

Authentication Problems

# Update remote URL to use SSH
git remote set-url origin git@github.com:username/repo.git

# Clear credential cache
git config --global --unset credential.helper

# Re-authenticate with GitHub CLI
gh auth login

Merge Conflicts

# Abort merge if needed
git merge --abort

# Use merge tool
git mergetool

# Configure merge tool
git config --global merge.tool vimdiff

Accidental Commits

# Undo last commit but keep changes
git reset --soft HEAD~1

# Undo and discard changes
git reset --hard HEAD~1

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

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GitHub Alternatives

GitLab

• Self-hosted or cloud
• Built-in CI/CD
• Free private repositories

Bitbucket

• Atlassian ecosystem
• Free for small teams
• Integrated with Jira

SourceForge

• Open source focus
• Free hosting
• Long-established platform

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Final Thoughts

Git and GitHub are essential tools for modern software development. Start with basic commands like add, commit, and push, then gradually learn advanced features like branching, merging, and collaboration workflows.

Pro Tip: Practice with personal projects first. Create a repository for your learning exercises, portfolio, or side projects. The more you use Git daily, the more natural it becomes.

Remember that Git is a powerful tool with many features. Don’t try to learn everything at once. Focus on the core workflow first, then expand your knowledge as you encounter new scenarios.

Next Steps:

1. Create your first GitHub repository
2. Set up SSH authentication
3. Practice the basic Git workflow
4. Contribute to an open-source project
5. Explore GitHub Actions for automation

Git and GitHub will become second nature with consistent practice. They’re not just tools—they’re essential skills that will serve you throughout your development career!