Moore's law

Moore's law is the prediction that the transistor density inside integrated circuits will double every two years, and that prices will decline at the same time. The phenomemon predicted by Moore's law, first described in 1965, has held remarkably true to date, and experts predict that this trend might continue until ~2020 or so, declining at the point where switching element sizes reach the molecular level. Moore's law is not really a law, but rather more a “rule of thumb” or a practical way to think about something.

Moore's law is named for Gordon Moore, a co-founder of Intel, who wrote about it in "Cramming more components onto integrated circuits", Electronics Magazine 19 April 1965:

The complexity for minimum component costs has increased at a rate of roughly a factor of two per year ... Certainly over the short term this rate can be expected to continue, if not to increase. Over the longer term, the rate of increase is a bit more uncertain, although there is no reason to believe it will not remain nearly constant for at least 10 years. That means by 1975, the number of components per integrated circuit for minimum cost will be 65,000. I believe that such a large circuit can be built on a single wafer

Although named for him, Gordon Moore may not have invented Moore's law; instead, he may have heard Douglas Engelbart, a co-inventor of the mechanical computer mouse, discuss the projected downscaling of integrated circuit size in a 1960 lecture.. Moore's observation was named a 'law' by the Caltech professor and VLSI pioneer Carver Mead.

In 1975, Moore projected a doubling only every two years. He is adamant that he never said "every 18 months", but that is how it has been quoted. The SEMATECH roadmap follows a 24 month cycle. In April 2005, Intel offered $10,000 for a copy of the original Electronics Magazine.

It has become common practice to cite Moore's Law as a predictor for the rapid advance in computing power per unit cost in a variety of computer-related technologies, such as hard disk storage cost per unit of information, even though such advances may have little to do with transistor technology advances. Moore's Law has become synonymous with saying "things very quickly gain capabilities, while cost falls".

A new important chapter started for Moore's law in 2003. The cycles per second for microprocessor went flat, and processors began to keep Moore's law alive by adding extra cores. multicore microprocessors in personal computers.

The problem of absolute power consumption has surfaced. The power consumption of computers is now a non-trivial fraction of each modern nation's total power output. (More than 1% and growing.) The current limitations to Moore's law are not due to hardware engineering but now place the burden on programmers to make use of multiple cores and the burden on society to pay the cost of the extra electrical load. In response, new metrics are being used to measure computation in terms of energy consumed.