Microprocessors and Microcomputers Although integrated circuits made computers smaller, the processing units still consisted of a number of circuits on separate chips. In 1971, an engineer working for Intel realized that a set of circuits commissioned for an electronic calculator could all be put onto one chip, and that the resulting device could be used as a general-purpose "computer on a chip". The result was the Intel 4004 the world's first microprocessor. Physically, it consisted of a silicon chip in a protective ceramic capsule, with a set of metal pins sticking out that connected it to other components in whatever device it controlled. It contained 2,300 transistors, executed 60,000 operations per second, and could be used for any device - including computers and robots - that required a "brain" for accepting input and following a program of instructions to produce an output. Within five years, many very powerful microprocessors had appeared.