Considered by many to be a direct forerunner of the modern computer, the Difference Engine was able to compute mathematical tables. This woodcut shows a small portion of the ingenious machine, which was designed by Charles Babbage in the 1820s. Although the device did not have a memory, Babbage’s later idea for the Analytical Engine would have been a true, programmable computer if the technology of his time had been able to build it.
Computer, machine that performs tasks, such as calculations or electronic communication, under the control of a set of instructions called a program. Programs usually reside within the computer and are retrieved and processed by the computer’s electronics. The program results are stored or routed to output devices, such as video display monitors or printers. Computers perform a wide variety of activities reliably, accurately, and quickly.