The first commercially successful microprocessor, introduced by Intel in 1971, was the Intel 4004.
Intel released the 4004 on November 15, 1971, as a 4-bit central processing unit. It was developed for Busicom’s 141-PF printing calculator and formed part of a chipset that also included memory and input/output components. The project began after Busicom asked Intel for a calculator-control design in 1969.
The 4004 was not the first electronic processor of any kind. Earlier systems used multiple chips, and some early processor designs were created for military or specialized equipment. The 4004’s landmark achievement was putting the essential CPU functions onto a single commercially available chip.
The Intel 8008 followed in 1972 as an 8-bit processor, while the Z80 and Motorola 6800 arrived later. The 4004’s design helped establish the single-chip microprocessor industry that eventually enabled personal computers and embedded electronics.