Attribute tracked time to a project. Group them under a client if you want to — anything you don’t assign stays in General.
Add a project
Only the name is required. Pick a client to file it under one, or leave it as No client.
Deleting a project leaves its hours where they are — they stay on the timesheet, marked as belonging to a project that no longer exists, rather than disappearing with it. Clients are managed on the Clients page.