The term 'Apple Desktop Computer' refers to two different types of computers manufactured by Apple Inc. The first is the MAC, which is a three-letter acronym for Macintosh. The MAC is a personal computer that was first released in 1984 and has since become one of the most popular desktop computers in the world. The second type of Apple Desktop Computer is the iMac, which is a four-letter acronym for 'Integrated MAC'. The iMac was first released in 1998 and is an all-in-one computer that combines the monitor, processor, and other components into a single unit. Both the MAC and iMac are popular choices for home and business users alike.