Apple applied for a US patent for the design of the Dock in 1999 and was granted the patent in October 2008, nearly a decade later. Any application can be dragged and dropped onto the Dock to add it to the dock, and any application can be dragged from the dock to remove it, except for Finder and Trash, which are permanent fixtures as the leftmost and rightmost items (or highest and lowest items if the Dock is vertically oriented), respectively. Part of the macOS Core Services, is located at .