A computer that follows a set of software instructions, which is essentially every computer. A general-purpose computer can perform any data processing operation that the instructions in a program tell it to do. However, there are countless appliances, gadgets, toys and devices with computer processors that follow only one set of instructions permanently built into the chip. Such computers are known as "microcontrollers." They are produced by the billions each year and are not user programmable. See
microcontroller and
computer.
Programmable Machines
Dating back to the 1800s, the first programmable machines were designed for calculations only and not general-purpose computing (see
Difference Engine and
Analytical Engine). In the 1930s and 1940s, programmable machines were still centered on calculations, often for military purposes (see
Z1,
ABC and
ENIAC). In the 1950s, Remington Rand made a name for itself with the general-purpose UNIVAC I business computer (see
UNIVAC I).