A microprocessor is a programmable component. It incorporates the functions of a central processing unit (CPU) on a single semi conducting integrated circuit (IC). The microprocessor was born by dipping the word size of the CPU from 32 bits to 4 bits, so that the transistors of its logic circuits would vigorous onto a single part. One or more microprocessors typically serve up as the CPU in a computer system, embedded system, or handheld device.
Microprocessors made probable the beginning of the microcomputer in the mid-1970s. Before this period, electronic CPUs were typically made from massive distinct switching devices (and later small-scale integrated circuits) containing the equivalent of only a few transistors. By integrating the processor onto one or a very few large-scale integrated circuit packages (containing the equivalent of thousands or millions of discrete transistors), the cost of processor power was greatly reduced. Since the dawn of the IC in the mid-1970s, the microprocessor has become the most rampant implementation of the CPU, nearly completely replacing all other forms. See History of computing hardware for pre-electronic and early electronic computers.