The Intel 400 is a microprocessor introduced by Intel in 1971, marking a significant advancement in computer technology. It was the first commercially available microprocessor, featuring a 4-bit architecture and capable of executing around 60,000 instructions per second. This innovation paved the way for the development of more complex computing systems. The Intel 400 was primarily used in calculators and early computer systems, helping to reduce the size and cost of electronic devices. Its introduction laid the foundation for future microprocessors, leading to the evolution of modern computing and the rise of personal computers.