Branches

A branch is a separate line of development. Think of it like a separate copy of a document:

• You have the main document (the main branch)
• You make a copy to experiment (a feature branch)
• If the experiment works, you merge it back

gitGraph
   commit id: "Initial setup"
   commit id: "Add navbar"
   branch feature-dark-mode
   checkout feature-dark-mode
   commit id: "Dark mode colors"
   commit id: "Dark mode toggle"
   checkout main
   commit id: "Fix header bug"
   checkout feature-dark-mode
   commit id: "Polish dark mode"

Result: main progresses normally while feature-dark-mode has its own commits. The branches diverge from a common ancestor.

# List all branches
git branch
# * main          (the * means you're on main)

# Create a new branch
git branch feature-login

# Switch to a branch
git checkout feature-login
# OR (modern way)
git switch feature-login

# Create and switch in one command
git checkout -b feature-login
git switch -c feature-login

# Rename a branch (while on it)
git branch -m new-name

# Delete a branch (after merging)
git branch -d feature-login

# Force delete (changes not merged)
git branch -D feature-login

A branch is just a pointer to a specific commit. When you make a new commit on a branch, the pointer moves forward.

Before creating a branch:
    main
      ▼
  ┌───┐   ┌───┐   ┌───┐
  │ A │──▶│ B │──▶│ C │
  └───┘   └───┘   └───┘

After creating feature-login (pointing to same commit):
    main
      ▼
  ┌───┐   ┌───┐   ┌───┐
  │ A │──▶│ B │──▶│ C │
  └───┘   └───┘   └───┘
                    ▲
              feature-login

After committing on feature-login:
    main
      ▼
  ┌───┐   ┌───┐   ┌───┐   ┌───┐
  │ A │──▶│ B │──▶│ C │──▶│ D │
  └───┘   └───┘   └───┘   └───┘
                            ▲
                      feature-login

• Isolate work — experiment without breaking the main code
• Collaborate — multiple people work on different features simultaneously
• Review — changes are reviewed before merging (pull requests)
• Organize — features, bug fixes, and experiments each have their own branch

• A branch is a separate line of development — like a copy of your project
• git branch <name> creates a branch; git switch <name> moves to it
• Use git switch -c <name> to create and switch in one step
• Branches let you work on features without affecting main
• Delete branches with git branch -d <name> after merging