Git is a distributed version control system designed to handle everything from small to very large projects with speed and efficiency. Git tracks changes in files and coordinates work among multiple developers, enabling collaborative software development while maintaining a complete history of changes.
Core Concepts
- Repository: Directory containing all project files and Git metadata
- Commit: Snapshot of project state at a specific point in time
- Branch: Independent line of development
- Merge: Combining changes from different branches
- Remote: Version of repository stored on a server
- Working Directory: Local directory where files are edited
- Staging Area: Area where changes are prepared before committing
Git Workflow
- Working Directory: Make changes to files in your local directory
- Staging Area: Add changes to the staging area (git add)
- Repository: Commit changes to the local repository (git commit)
- Remote Repository: Push changes to remote repository (git push)
- Syncing: Pull changes from remote repository (git pull)
Key Commands
- git init: Initialize a new Git repository
- git clone: Create a local copy of a remote repository
- git add: Add files to the staging area
- git commit: Save changes to the repository
- git push: Upload local commits to a remote repository
- git pull: Download and merge changes from a remote repository
- git status: Show the status of files in the working directory
- git log: Display commit history
- git branch: List, create, or delete branches
- git checkout: Switch between branches or restore files
- git merge: Combine changes from different branches
- git diff: Show changes between commits, commit and working tree, etc.
Branching and Merging
- Branching: Create separate lines of development for features or fixes
- Master/Main Branch: Primary branch containing stable code
- Feature Branches: Branches for developing new features
- Hotfix Branches: Branches for urgent fixes to production code
- Merge Conflicts: Occur when changes conflict during merge
- Rebasing: Alternative to merging that replays commits
Distributed Development
- Local Operations: Most Git operations are local and fast
- Complete History: Each clone contains full repository history
- Offline Work: Work on commits locally without network access
- Redundancy: Multiple copies of repository exist across systems
- Peer-to-Peer: Developers can share changes directly
Git vs Other Version Control Systems
| System | Git | Other Systems |
|---|---|---|
| Git vs SVN | Distributed | Centralized |
| Git vs Mercurial | Higher market adoption | Both distributed |
| Git vs Perforce | Open-source | Commercial |
| Git vs CVS | More modern and feature-rich | Older system |
| Git vs TFS | Distributed and open-source | Microsoft's centralized system |
Benefits
- Speed: Fast operations due to local repository
- Flexibility: Multiple branching and merging strategies
- Security: Cryptographic hashing ensures data integrity
- History: Complete history of all changes
- Collaboration: Multiple developers can work simultaneously
- Backup: Multiple copies provide redundancy
- Experimentation: Easy to create branches for experimental features
Advanced Features
- Stashing: Temporarily save changes without committing
- Rebasing: Integrate changes by replaying commits
- Hooks: Scripts that run automatically at certain points
- Submodules: Include other Git repositories as subdirectories
- Reflog: Reference log of updates to branch tips
- Cherry-pick: Apply specific commits to current branch
Git Workflows
- Centralized Workflow: Single central repository
- Feature Branch Workflow: Branches for each feature
- Gitflow Workflow: Structured branching model
- Forking Workflow: Each developer has their own fork
Best Practices
- Descriptive Commits: Write clear, descriptive commit messages
- Frequent Commits: Make small, focused commits regularly
- Branching Strategy: Use a consistent branching strategy
- Pull Before Push: Always pull latest changes before pushing
- Regular Pushing: Push changes regularly to backup and share
- Ignore Files: Use .gitignore to exclude unnecessary files
- Tags: Use tags for version releases
Common Git Hosting Platforms
- GitHub: Popular platform with collaboration features
- GitLab: Complete DevOps platform with Git hosting
- Bitbucket: Atlassian's Git repository hosting
- Self-hosted: GitLab, Gitea, or plain Git server