Information Technology Reference
In-Depth Information
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Beginnings of a revolution
Computer science also differs from physics in
that it is not actually a science. It does not study
natural objects. Neither is it, as you might think,
mathematics. Rather, computer science is about
getting something to do something. . . .
Richard Feynman
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What is computer science?
It is commonplace to say that we are in the midst of a computing revolu-
tion. Computers are impacting almost every aspect of our lives. And this is just
the beginning. The Internet and the Web have revolutionized our access to
information and to other people. We see computers not only providing intel-
ligence to the safety and performance of such things as cars and airplanes,
but also leading the way in mobile communications, with present-day smart
phones having more computing power than leading-edge computers only a
decade ago. This topic tells the story how this all came about, from the early
days of computers in the mid-1900s, to the Internet and the Web as we know it
today, and where we will likely be in the future.
The academic field of study that encompasses these topics draws from mul-
tiple disciplines such as mathematics and electronics and is usually known as
computer science
. As Nobel Prize recipient, physicist Richard Feynman says in the
quotation that introduces this chapter, computer science is not a science in
the sense of physics, which is all about the study of natural systems; rather, it
is more akin to engineering, since it concerns the study of man-made systems
and ultimately is about getting computers to do useful things. Three early com-
puting pioneers, Allen Newell, Alan Perlis, and Herbert Simon, were happy to
use science to describe what they did, but put forward a similar definition to
Feynman: computer science is the study of computers. As we shall see, com-
puter science has much to do with the management of complexity, because
modern-day computers contain many billions of active components. How can
such complex systems be designed and built? By relying on the principles of
hierarchical abstraction
and
universality
, the two main themes that underlie our
discussion of computers.
Hierarchical abstraction is the idea that you can break down the design
of a computer into layers so that you can focus on one level at a time without
having to worry about what is happening at the lower levels of the hierarchy.
Feynman in his
Lectures on Computation
makes an analogy with geology and the
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