Parallel Timelines

Creating Alternate Realities

Branching lets you diverge from the main timeline to experiment, develop features, or fix bugs—all without affecting the stable code. It's Git's killer feature.

What is a Branch?

A branch is a lightweight movable pointer to a commit. The default branch is main (or master). Creating a branch costs nothing and takes milliseconds.

Why Branch?

• Work on features without breaking main code
• Experiment safely
• Collaborate without conflicts
• Organize work logically
• Test ideas before committing to them

Viewing Branches

git branch          # List local branches
git branch -a       # List all branches (including remote)
git branch -v       # Show last commit on each branch

Creating a Branch

git branch feature-navigation

This creates a new branch but doesn't switch to it.

Switching Branches

git checkout feature-navigation

Or with newer Git:

git switch feature-navigation

Create and Switch in One Command

git checkout -b feature-propulsion
# Or
git switch -c feature-propulsion

Branch Naming Conventions

Common patterns:

• feature/add-dark-mode
• bugfix/fix-login-timeout
• hotfix/critical-security-patch
• experiment/try-new-algorithm

Use descriptive names. Avoid spaces and special characters.

Working on a Branch

1. Create and switch: git switch -c my-feature
2. Make changes and commit normally
3. Push branch: git push -u origin my-feature

These commits only affect your branch, not main.

Deleting Branches

After merging a feature:

git branch -d feature-name     # Safe delete (only if merged)
git branch -D feature-name     # Force delete

Delete remote branch:

git push origin --delete feature-name

Branch Workflow Example

# Start on main
git switch main
git pull

# Create feature branch
git switch -c feature-sensors

# Work on feature (multiple commits)
git add sensors.js
git commit -m "Add temperature sensor"
git add sensors.js
git commit -m "Add pressure sensor"

# Push feature branch
git push -u origin feature-sensors

# Create pull request on GitHub
# After approval and merge, clean up
git switch main
git pull
git branch -d feature-sensors

Viewing Branch History

git log --oneline --graph --all

Visualizes all branches and their relationships.

Comparing Branches

git diff main..feature-branch

Renaming Branches

git branch -m old-name new-name

Branch Best Practices

• Keep main stable and deployable
• Create branches for each feature/fix
• Merge or delete branches when done
• Pull main regularly into long-running feature branches
• Use descriptive branch names
• Don't commit directly to main on team projects

Next: Timeline Convergence

You can create parallel timelines. Now learn to merge them back together!