Moore’s Law


Every field has its rules of thumb, brief formulas or relationships that are useful for quick estimates and back-of -the envelope calculations. Rarely do these maxims become popular knowledge, and even more rarely do they become as ubiquitous and influential as Moore’s Law has been in the computer industry. Moore’s Law is generally understood to predict that the number of transistors  that can be placed on a single microchip will double every year or two. Now a feature in popular technical writing, Moore’s Law is often credited as a driving  factor in the digital age.


On the left is Moore’s original 1965 graph. There are only four datapoints that form the basis of Moore’s Law! On the right is Moore’s 1975 graph. There is a gap from the mid 1960s to the 1970s, where no chips met his prediction

Moore’s Law is named after Dr. Gordon E. Moore, a physical chemist who co-founded two of the most important semiconductor companies of their time, Intel and Fairchild Semiconductor. Moore first articulated what would later be identified as his law in a 1965 paper for Electronics magazines thirty-fifth anniversary. He noted that the number of transistors that could be placed on a chip had been doubling every year, and that he expected the trend to continue until 1975.

Moore’s prediction turned out to be very accurate, and he presented another paper on his law at an industry conference in 1975. There, Moore revised the  law, changing the expected doubling time to approximately two years. According to popular belief, the pace of increasing transistor density has held closely to this forecast ever since, despite changes in both technologies and the nature of the semiconductor business.

…except this is not quite the whole story. Instead, as you can see in my paper, Establishing Moore’s Law,  the law has been repeatedly reinterpreted over the early years of its operation, making it seem more correct than it actually was, and giving it the mystical quality that made it a self-fulfilling prophecy for industry planning once Japanese semiconductor companies entered the market in the late 1970s.

Intel’s page has several original documents, including the 1965 and 1975 papers. IEEE has a piece on the technical implications of Moore’s Law.