Branch
In plain terms
A separate line of development in version control.
Going deeper
A branch lets you work on a feature or fix in isolation from the main code, then merge it back when ready. Branching enables parallel work without stepping on others.
Under the hood
A lightweight movable pointer to a commit; cheap branching enables feature isolation, but long-lived branches accumulate painful merge conflicts.
Examples
main/master, feature/login, hotfix branches, git branch/checkout/switch.
Think of it like...
Like writing a draft chapter in a separate notebook, so the main manuscript stays clean until you're ready to fold it in.