macintosh computer in 1984 and designed it to be lower in cost. it was the first commercially successful product to use a multi-panel window interface. a desktop metaphor was used, in which files looked like pieces of paper, file directories looked like file folders, there were a set of desk accessories like a calculator, notepad, and alarm clock that the user could place around the screen as desired, and the user could delete files and folders by dragging them to a trash-can icon on the screen.