What is computer science?

It is commonplace to say that we are in the midst of a computing revolution. 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 intelligence 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 book 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 multiple 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 computing 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, computer 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.