From
Moore's Law (investopedia):
Understanding Moore's Law
In 1965, Gordon E. Moore—co-founder of
Intel (NASDAQ: INTC)—postulated that the number of transistors
that can be packed into a given unit of space will double about every two years
Moore's Law's Impending End
Experts agree that computers should reach the physical limits of Moore's Law at some point in the 2020s. The high temperatures of transistors eventually would make it impossible to create
smaller circuits. This is because cooling down the transistors takes more energy than the amount of energy that already passes through the transistors. In a 2007 interview, Moore himself admitted that "...the fact that materials are made of atoms is the fundamental limitation and it's not that far away...We're pushing up against some fairly fundamental limits so one of these days
we're going to have to stop making things smaller."
==
The definition of Moore's Law provided in the above shows it is not just doubling of transistors but that doubling happens within a given unit of space ie the
density of transistors doubles every two years.
The following definition agrees with that:
"More precisely, the law is an empirical observation that the
density of semiconductor integrated circuits one can most economically manufacture doubles about every 2 years."
Wikipedia's article has cited references for the following:
"Moore posited a log-linear relationship between device complexity (
higher circuit density at reduced cost) and time."
"Moore wrote only about the
density of components, "a component being a transistor, resistor, diode or capacitor" at minimum cost."
And here is a line straight from Moore's own paper: "Such a
density of components can be achieved by present optical techniques and does not require the more exotic techniques, such as electron beam operations, which are being studied to make even smaller structures."
Moore's Law is about the density of components doubling very year originally with the current version every two years.
