 Version-control branch

A version-control branch names a line of development that can progress alongside another. In Git, a branch is a movable reference to a commit; it does not require an independent copy of every file. New commits normally advance the currently checked-out branch while older commits remain part of its ancestry.^[ref]

For example, two branch names can initially reference the same commit. Committing a change on one moves that reference and leaves the other at its old commit. Their shared history is represented once in the commit graph. Deleting a branch name therefore removes a reference rather than automatically erasing every commit it once named; reachability from other references and later storage management determine which objects remain available.