desktop (desktop computer, worktop)
1. An entire computer that sits on a desk or table, a PC or Macintosh being examples. It usually consists of: a display, either color or monochrome; a system box containing the processor, memory, disk drives, power supply, and communication interfaces; a keyboard; a pointing device, often a mouse. Although the desktop computer is relatively cumbersome compared with a notebook computer of equivalent power, it currently has a significantly better power/performance ratio.

2. Part of a graphical user interface which invites the user to imagine that some or all of the screen is an actual desktop on which actions analogous to those occurring on a physical desktop can be carried out. These include the opening and closing of folders, the entry and modification of text, the disposal of unwanted material into a wastebasket, and the use of communication systems analogous to telephones and mailboxes. The analogy is supposed to make life easier for office workers unused to computers.

desk·top / ˈdeskˌtäp/ • n. the working surface of a desk. ∎  [as adj.] denoting a piece of equipment such as a microcomputer that is suitable for use at an ordinary desk: a desktop machine. ∎  a desktop computer. ∎  the working area of a computer screen regarded as a representation of a notional desktop and containing icons representing items such as files and a wastebasket.