Wastholm.com

In its simplest form, git worktree add <path> automatically creates a new branch whose name is the final component of <path>, which is convenient if you plan to work on a new topic. For instance, git worktree add ../hotfix creates new branch hotfix and checks it out at path ../hotfix. To instead work on an existing branch in a new worktree, use git worktree add <path> <branch>. On the other hand, if you just plan to make some experimental changes or do testing without disturbing existing development, it is often convenient to create a throwaway worktree not associated with any branch. For instance, git worktree add -d <path> creates a new worktree with a detached HEAD at the same commit as the current branch.

If a working tree is deleted without using git worktree remove, then its associated administrative files, which reside in the repository (see "DETAILS" below), will eventually be removed automatically (see gc.worktreePruneExpire in git-config[1]), or you can run git worktree prune in the main or any linked worktree to clean up any stale administrative files.