Git Basics

Welcome to the world of Git! Forget GUIs for a moment and embrace the power of the command line. This guide will walk you through the essential commands to make you a Git wizard.

---

1. The Genesis: git clone

Every great journey begins with a single step. In Git, it starts with clone. This command copies an existing repository from GitHub to your local machine.

How to use it:

# Clones a repository into a new directory
git clone https://github.com/<repository-owner>/<repository-name>.git

You now have a complete local copy of the project, history and all.

---

2. The Workspace: status, add, and commit

This is your daily bread and butter. You've made some changes, and now you need to save them.

git status

Checks the status of your working directory. It shows which files are modified, which are new (untracked), and which are staged.

How to use it:

# See what's changed since your last commit
git status

git add

Adds your changes to the "staging area". Think of this as a waiting room for your commits. You can add specific files or all of them.

How to use it:

# Add a specific file
git add path/to/your/file

# Add all modified and new files in the current directory (Think twice before using this!)
git add .

git commit

Saves your staged changes to your local repository's history. A commit is a snapshot of your code at a specific point in time. Always write a clear, concise commit message!

How to use it:

# Commit your staged changes with a message
git commit -m "feat: Implement the new login feature"

---

3. Collaboration: push and pull

You've saved your work locally. Now it's time to share it with your team or sync up with their changes.

git push

Uploads your committed changes from your local repository to the GitHub repository.

How to use it:

# Push your changes to the 'main' branch on the 'origin' remote
git push origin main

git pull

Fetches changes from the remote repository and merges them into your current local branch. It's how you get the latest updates from others.

How to use it:

# Pull the latest changes from the 'main' branch
git pull origin main

---

4. Parallel Universes: branch and checkout

Branches let you work on new features or bug fixes in an isolated environment without affecting the main codebase.

git branch

Lists all branches in your repository. You can also use it to create or delete branches.

How to use it:

# List all branches
git branch

# Create a new branch called 'new-feature'
git branch new-feature

git checkout

Switches between different branches.

How to use it:

# Switch to the 'new-feature' branch
git checkout new-feature

# You can also create and switch to a new branch in one command!
git checkout -b another-new-feature

---

5. The Convergence: merge

Once your feature is complete and tested in its branch, you can merge it back into the main branch.

git merge

Combines the history of two branches. You first checkout the branch you want to merge into (e.g., main), and then run merge with the name of the branch you want to merge from.

How to use it:

# First, switch to the main branch
git checkout main

# Then, merge the 'new-feature' branch into main
git merge new-feature

---

6. The Time Machine: log

Want to see the history of your project? git log is your DeLorean.

git log

Shows a log of all the commits in your repository's history.

How to use it:

# Show the full commit history
git log

# Show a more condensed version of the log
git log --oneline --graph --decorate

---

7. A Typical Team Workflow

So how does this all fit together in a team? Here's a common sequence of events for a developer starting a new task.

Step 1: Get the latest code

Before starting, make sure your local main branch is up-to-date with the remote repository.

# Switch to the main branch
git checkout main

# Pull the latest changes
git pull origin main

Step 2: Create your own branch

Create a new branch to work on your feature in isolation.

# Create and switch to a new branch for your feature
git checkout -b new-feature-sprint-5

Step 3: Do your work (Code, code, code!)

Make all your code changes for the new feature. Once you're ready, save your work.

# Check the status of your changes
git status

# Add your changed files to the staging area
git add .

# Commit your changes with a descriptive message
git commit -m "feat: Implement user authentication"

Step 4: Push your branch to GitHub

Share your new feature branch with the remote repository.

# Push your branch
git push origin new-feature-sprint-5

Step 5: Create a Pull Request (PR)

Go to the repository on GitHub. You'll see a prompt to create a Pull Request from your new-feature-sprint-5 branch to the main branch. Open the PR, describe your changes, and request a review from your teammates.

Once your PR is approved and merged, your code is now part of the main branch! You can now go back to Step 1 for your next task.

---

Happy coding!