Intel 4004

The Intel 4004 was one of the first microprocessors ever produced, released in 1971. The 4004 was designed by Federico Faggin, Masatoshi Shima and others. 

During the development of the 4004, few people foresaw the potential of microprocessors as integral components in computers for use by the general public. The 4004, which was part of the MCS-4 family of chips, was developed mainly for use in calculators, cash registers, ATMs (automatic teller machines) and other simple business systems.

The 4004 had a 4-bit processor. The instructions were stored in ROM (read-only memory), while the data was stored in an external register. The 4004 used a 4-bit address bus. Other features included:

• Maximum clock speed of 740 kHz.
• Up to 92600 instructions per second.
• Separate program and data storage.
• 12-bit addresses.
• 8-bit instructions.
• 4-bit words.

One of the most noteworthy aspects of this microprocessor was the so-called silicon gate structured design method, which made it possible to design smaller and more efficient chips than previously possible.