Branches are Git’s superpower. They let you work on a new feature or fix without touching the stable code everyone else depends on. This is how entire teams work on one project at the same time.

🎯 Learning Objectives

By the end of this lesson you will:

• Create and switch between branches
• Merge branches back together
• Understand and resolve a merge conflict
• Collaborate using pull requests on GitHub

Working with Branches

git branch                     # list branches
git switch -c feature-login    # create + switch to a new branch
git switch main                # switch back to main

Switched to a new branch 'feature-login'

Think of main as the trusted, always-working version. You build on a branch, then merge it back when it’s ready.

Merging

Once your feature works, merge it into main:

git switch main
git merge feature-login

If no one else changed the same lines, Git merges cleanly.

Resolving a Merge Conflict

A conflict happens when two branches change the same lines. Git pauses and marks the file:

<<<<<<< HEAD
Welcome to our app!
=======
Welcome to the DevOps Hub!
>>>>>>> feature-login

Edit the file to keep what you want, remove the <<<, ===, >>> markers, then:

git add index.html
git commit -m "Resolve merge conflict in index.html"

The Pull Request Workflow

On a team you rarely merge straight into main. Instead:

git switch -c feature-login
# ... make changes, commit ...
git push -u origin feature-login

Then on GitHub you open a Pull Request (PR) — a request to merge your branch into main. A PR lets teammates review the code, comment, and approve before it’s merged, and it’s what usually triggers your CI/CD pipeline.

🧪 Hands-on Lab

Switched to a new branch 'feature-x'
Switched to branch 'main'
Updating a1b2c3d..d4e5f6g
Fast-forward
README.md | 1 +

🧠 Knowledge Check

💼 Interview Preparation

🎉 Section Complete

You can now branch, merge, resolve conflicts, and collaborate through pull requests — the daily workflow of every DevOps team. Next we head into the cloud with AWS.