A microprocessor is a tiny piece of silicon containing millions of transistors that can perform the functions of electronic devices. The first commercial microprocessor was the Intel 4004 from 1971. As technology advanced, microprocessors increased in power and performance with higher bit sizes and more transistors. A microprocessor has a control unit that directs other components like a bus interface unit, execution unit, registers, and cache to fetch and execute instructions. Computing occurs as the instruction fetch and decode unit obtains instructions from cache, which are then operated on by the ALU or FPU and results are written to registers or cache. Microprocessors are essential components that control modern electronic systems.