The most popular formulation is of the doubling of the number of transistors on integrated circuits every 18 months. At the end of the 1970s, Moore's Law became known as the limit for the number of transistors on the most complex chips. However, it is also common to cite Moore's Law to refer to the rapidly continuing advance in computing power per unit cost, because increase in transistor count is also a rough measure of computer processing power.
The implications of Moore's Law for computer component suppliers are very significant. A typical major design project (such as an all-new CPU or hard drive) takes between two and five years to reach production-ready status. In consequence, component manufacturers face enormous timescale pressures—just a few weeks of delay in a major project can spell the difference between great success and massive losses, even bankruptcy. Expressed as "a doubling every 18 months", Moore's Law suggests the phenomenal progress of technology in recent years. Expressed on a shorter timescale, however, Moore's Law equates to an average performance improvement in the industry as a whole of close to 1% per week. For a manufacturer competing in the competitive CPU market, a new product that is expected to take three years to develop and is just three or four months late is 10 to 15% slower, bulkier, or lower in storage capacity than the directly competing products, and is usually unsellable. (If instead we accept that performance doubles every 24 months, rather than every 18 months, a 3 to 4 month delay would mean 8 to 11% less performance
2. From http://www.webopedia.com/TERM/M/Moores_Law.html
The observation made in 1965 by Gordon Moore, co-founder of Intel, that the number of transistors per square inch on integrated circuits had doubled every year since the integrated circuit was invented. Moore predicted that this trend would continue for the foreseeable future. In subsequent years, the pace slowed down a bit, but data density has doubled approximately every 18 months, and this is the current definition of Moore's Law, which Moore himself has blessed. Most experts, including Moore himself, expect Moore's Law to hold for at least another two decades.
3. From http://www.answers.com/topic/moore-s-law
"The number of transistors and resistors on a chip doubles every 18 months." By Intel co-founder Gordon Moore regarding the pace of semiconductor technology. He made this famous comment in 1965 when there were approximately 60 devices on a chip. Proving Moore's law to be rather accurate, four decades later, Intel placed 1.7 billion transistors on its Itanium chip.
In 1975, Moore extended the 18 months to 24 months. More recently, he said that the cost of a semiconductor manufacturing plant doubles with each generation of microprocessor. See laws