Gordon Moore, who along with Robert Noyce and Andy Grove founded Intel in 1968, made the observation that the total number of transistors occupying a square inch of integrated circuit material had doubled every year since the invention of the microchip and that this trend would continue.
Moore's observation was formalised into what is now known as Moore's Law and it proved accurate up until the late 1970s when the time span was modified from one year to eighteen months for the observation to remain accurate.
Click on this link to review the wikipedia article on CPUs.
Click on this link to review the wikipedia article on Moore's Law.
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