Git 101
Essential Git Commands for Repository Management
Git is the backbone of modern software development, enabling developers to track changes, collaborate seamlessly, and maintain project history. Understanding the core Git commands and workflow is crucial for any developer working with version control.
Understanding Git's Architecture
Before diving into commands, it's important to understand Git's four-stage architecture:
- Working Directory: The directory where you make changes to files
- Staging Area: Controls which changes go into a commit
- Local Repository: The version of a project stored on your local machine
- Remote Repository: The version of a project stored on a server (like GitHub)
Essential Git Commands
1. git add
Adds changes from the working directory into the staging area.
git add filename.txt # Add specific file
git add . # Add all changes
git add *.js # Add all JavaScript files
2. git commit
Saves a snapshot of currently staged changes in the local repository with a descriptive message.
git commit -m "Add user authentication feature"
git commit -am "Fix login bug" # Add and commit in one step
3. git push
Uploads committed changes from the local repository to a remote repository.
git push origin main # Push to main branch
git push origin feature-branch # Push to specific branch
git push -u origin main # Set upstream and push
4. git fetch
Downloads changes from a remote repository without applying them locally.
git fetch origin # Fetch from origin
git fetch --all # Fetch from all remotes
5. git merge
Combines changes from one branch into another.
git merge feature-branch # Merge feature-branch into current branch
git merge origin/main # Merge remote main into current branch
6. git pull
Fetches and then merges changes from a remote repository into the local branch.
git pull origin main # Pull from remote main
git pull # Pull from tracked branch
7. git diff
Shows changes not staged or committed yet.
git diff # Show unstaged changes
git diff --cached # Show staged changes
git diff filename.txt # Show changes in specific file
8. git diff HEAD
Shows changes between the current working directory and the latest commit.
git diff HEAD # Compare with latest commit
git diff HEAD~1 # Compare with previous commit
9. git status
Shows the current state of the working directory and staging area.
git status # Full status
git status -s # Short status format
10. git branch
Lists all local branches and shows the current branch.
git branch # List local branches
git branch -a # List all branches (local and remote)
git branch new-feature # Create new branch
git branch -d old-branch # Delete branch
11. git checkout
Creates a branch or switches between branches.
git checkout main # Switch to main branch
git checkout -b new-feature # Create and switch to new branch
git checkout -- filename.txt # Discard changes in file
12. git log
Shows commits in the current branch with detailed information.
git log # Full commit history
git log --oneline # Condensed format
git log --graph # Show branch structure
git log -5 # Show last 5 commits
13. git stash
Temporarily saves uncommitted changes and applies them later.
git stash # Stash current changes
git stash pop # Apply and remove latest stash
git stash list # List all stashes
git stash apply stash@{0} # Apply specific stash
14. git rebase
Applies commits from one branch to another, creating a linear history.
git rebase main # Rebase current branch onto main
git rebase -i HEAD~3 # Interactive rebase last 3 commits
15. git reset
Undoes changes in the working directory and moves back to a specific commit.
git reset HEAD~1 # Undo last commit, keep changes
git reset --hard HEAD~1 # Undo last commit, discard changes
git reset filename.txt # Unstage specific file
16. git revert
Undoes changes by creating a new commit that reverses previous changes.
git revert HEAD # Revert last commit
git revert abc123 # Revert specific commit
17. git cherry-pick
Applies specific commits from one branch to another.
git cherry-pick abc123 # Apply specific commit
git cherry-pick abc123..def456 # Apply range of commits
Common Workflows
Basic Development Workflow
# 1. Check current status
git status
# 2. Add changes to staging
git add .
# 3. Commit changes
git commit -m "Implement new feature"
# 4. Push to remote
git push origin main
Feature Branch Workflow
# 1. Create and switch to feature branch
git checkout -b feature/user-auth
# 2. Make changes and commit
git add .
git commit -m "Add user authentication"
# 3. Push feature branch
git push origin feature/user-auth
# 4. Switch back to main and merge
git checkout main
git merge feature/user-auth
# 5. Clean up
git branch -d feature/user-auth
Collaboration Workflow
# 1. Fetch latest changes
git fetch origin
# 2. Update local main
git checkout main
git pull origin main
# 3. Create feature branch from updated main
git checkout -b feature/new-functionality
# 4. Work and push
git add .
git commit -m "Add new functionality"
git push origin feature/new-functionality
Best Practices
- Commit frequently with descriptive messages
- Pull before pushing to avoid conflicts
- Use branches for features and experiments
- Review changes with
git diffbefore committing - Keep commits atomic - one logical change per commit
- Use meaningful branch names like
feature/user-loginorbugfix/memory-leak
Conclusion
Mastering these essential Git commands will significantly improve your development workflow and collaboration capabilities. Start with the basic commands (add, commit, push, pull) and gradually incorporate more advanced features like branching, rebasing, and stashing as your projects grow in complexity.
Remember, Git is a powerful tool that becomes more valuable the more you understand its underlying concepts. Practice these commands regularly, and you'll soon find yourself navigating version control with confidence.