… Figure 2b gives the introduction price and date of the first or defining computer of a class.
Here, I will use the aspects of Bell’s Law described previously and follow a timeline of the
class formations beginning with the establishment of the first computer classes (mainframe,
supercomputer, shared personal professional computers or workstations, and
minicomputers) using vacuum tubes, transistors, and bipolar integrated circuits that
continue through the mid-1990s in the first period (1951–1990). In the second period …

In 1951 a man could walk inside a computer. By 2010, a computer cluster with millions of
processors will have expanded to building size. In this new paper Gordon Bell explains the
history of the computing industry, positing a general theory (" Bell's Law) for the creation,
evolution, and death of computer classes since 1951. Using the exponential transistor
density increases forecast by Moore's Law in 1965 and 1975 as the principal basis for the
life cycle of computer classes after the microprocessor was introduced in 1971, he predicts …