A desktop computer (or desktop PC) is a computer that is designed to stay in a single location. It may be a tower (also known as a system unit) or an all-in-one machine, such as an iMac. Unlike laptops and other portable devices, desktop computers cannot be powered from an internal battery and therefore must remain connected to a wall outlet.
In the early age of computers, desktop computers were the only personal computers available. Since laptops and tablets did not exist, all home PCs were desktop computers. Still, the term "desktop computer" was used back then to differentiate between personal PCs and larger computers, such as mainframes and supercomputers.
While desktop computers were the most popular type of personal computer for several decades, in recent years, laptop sales have surpassed those of desktop PCs. Because of the rise in mobile computing, this trend is likely to continue. However, desktop computers remain the most popular choice for business workstations and family computers.