HISTORY OF COMPUTERS AND THE INTERNET
Steps Toward Modern Computing 31 First Steps: Calculators 31 The Technological Edge: Electronics 31 Putting It All Together: The ENIAC 36 The Stored-Program Concept 36 The Computer’s Family Tree 37 The First Generation (1950s) 37 The Second Generation (Early 1960s) 38 The Third Generation (Mid-1960s to Mid-1970s) 39 The Fourth Generation (1975 to the Present) 41 A Fifth Generation? 44 The Internet Revolution 45 Lessons Learned 48
WHAT YOU’LL LEARN . . .
After reading this module, you will be able to: 1. Define the term “electronics” and describe some early electronic devices that helped launch the computer industry. 2. Discuss the role that the stored-program concept played in launching the commercial computer industry. 3. List the four generations of computer technology. 4. Identify the key innovations that characterize each generation. 5. Explain how networking technology and the Internet has changed our world. 6. Discuss the lessons that can be learned from studying the computer’s history.
History of Computers and the Internet
What would the world be like if the British had lost to Napoleon in the battle of Waterloo, or if the Japanese had won World War II? In The Difference Engine, authors William Gibson and Bruce Sterling ask a similar question: What would have happened if nineteenth-century inventor Charles Babbage had succeeded in creating the world’s first automatic computer? (Babbage had the right idea, but the technology of his time wasn’t up to the task.) Here is Gibson and Sterling’s answer: with the aid of powerful computers, Britain becomes the world’s first technological superpower. Its first foreign adventure is to intervene in the American Civil War on the side of the U.S. South, which splits the United States into four feuding republics. By the mid-1800s, the world is trying to cope with the multiple afflictions of the twentieth century: credit cards, armored tanks, and fast-food restaurants. Alternative histories are fun, but history is serious business. Ideally, we would like to learn from the past. Not only do historians urge us to study history, but computer industry executives also say that knowledge of the computer’s history gives them an enormous advantage. In its successes and failures, the computer industry has learned many important lessons, and industry executives take these to heart. Although the history of analog computers is interesting in its own right, this module examines the chain of events that led to today’s digital computers. You’ll begin by looking at the computing equivalent of ancient history, including the first mechanical calculators and their huge, electromechanical offshoots that were created at the beginning of World War II. Next, you’ll examine the technology—electronics—that made today’s computers possible, beginning with what is generally regarded to be the first successful electronic computer, the ENIAC of the late 1940s. You’ll then examine the subsequent history of electronic digital computers, divided into four “generations” of distinctive—and improving—technology. The module concludes by examining the history of the Internet and the rise of electronic commerce.
STEPS TOW ARD MODERN COMPUTING
Today’s electronic computers are recent inventions, stemming from work that began during World War II. Yet the most basic idea of computing—the notion of representing data in a physical object of some kind, and getting a result by manipulating the object in some way—is very old. In fact, it may be as old as humanity itself. Throughout the ancient world, people used devices such as notched bones, knotted twine, and the abacus to represent data and perform various sorts of calculations (see Figure 1B.1).
First Steps: Calculators
During the sixteenth and seventeenth centuries, European mathematicians developed a series of calculators that used clockwork mechanisms and cranks (see Figure 1B.1). As the ancestors of today’s electromechanical adding machines, these devices weren’t computers in the modern sense. A calculator is a machine that can perform arithmetic functions with numbers, including addition, subtraction, multiplication, and division.
The Technological Edge: Electronics
Today’s computers are automatic, in that they can perform most tasks without the need for human intervention. They require a type of technology that was unimaginable in the nineteenth century. As Figure 1B.1 shows, nineteenth-century inventor Charles Babbage came up with the first design for a
Steps Toward Modern Computing: A Timeline
quipa (15th and 16th centuries) At the height of their empire, the Incas used complex chains of knotted twine to represent a variety of data, including tribute payments, lists of arms and troops, and notable dates in the kingdom’s chronicles.
abacus (4000 years ago to 1975) Used by merchants throughout the ancient world. Beads represent figures (data); by moving the beads according to rules, the user can add, subtract, multiply, or divide. The abacus remained in use until a worldwide deluge of cheap pocket calculators put the abacus out of work, after being used for thousands of years.
Jacquard's loom (1804) French weaver Joseph-Marie Jacquard creates an automatic, programmable weaving machine that creates fabrics with richly detailed patterns. It is controlled by means of punched cards. Pascal’s calculator (1642) French mathematician and philosopher Blaise Pascal, the son of an accountant, invents an adding machine to relieve the tedium of adding up long columns of tax figures.
Leibniz’s calculator (1674) German philosopher Gottfried Leibniz invents the first mechanical calculator capable of multiplication.
Hollerith’s tabulating machine (1890) Created to tally the results of the U.S. Census, this machine uses punched cards as a data input mechanism. The successor to Hollerith’s company is International Business Machines (IBM).
Babbage’s difference engine (1822) English mathematician and scientist Charles Babbage designs a complex, clockwork calculator capable of solving equations and printing the results. Despite repeated attempts, Babbage was never able to get the device to work.
Mark I (1943) In a partnership with Harvard University, IBM creates a huge, programmable electronic calculator that used electromechanical relays as switching devices. Zuse’s Z1 (1938) German inventor Konrad Zuse creates a programmable electronic calculator. An improved version, the Z3 of 1941, was the world’s first calculator capable of automatic operation.
Introducing Computers and the Internet
recognizably-modern computer. It would have used a clockwork mechanism, but the technology of his day could not create the various gears needed with the precision that would have been required to get the device to work. The technology that enables today’s computer industry is called electronics. In brief, electronics is concerned with the behavior and effects of electrons as they pass through devices that can restrict their flow in various ways. The earliest electronic device, the vacuum tube, is a glass tube, emptied of air, in the flow of electrons that can be controlled in various ways. Created by Thomas Edison in the 1880s, vacuum tubes can be used for amplification, which is why they powered early radios and TVs, or switching, their role in computers. In fact, vacuum tubes powered all electronic devices (including stereo gear as well as computers) until the advent of solidstate devices. Also referred to as a semiconductor, a solid-state device acts like a vacuum tube, but it is a “sandwich” of differing materials that are combined to restrict or control the flow of electrical current in the desired way.
Putting It All Together: The ENIAC
With the advent of vacuum tubes, the technology finally existed to create the first truly modern computer—and the demands of warfare created both the funding and the motivation. In World War II, the American military needed a faster method to calculate shell missile trajectories. The military asked Dr. John Mauchly (1907–1980) at the University of Pennsylvania to develop a machine for this purpose. Mauchly worked with a graduate student, J. Presper Eckert (1919–1995), to build the device. Although commissioned by the military for use in the war, the ENIAC was not completed until 1946, after the war had ended (see Figure 1B.2). Although it was used mainly to solve challenging math problems, ENIAC was a true programmable digital computer rather than an electronic calculator. One thousand times faster than any existing calculator, the ENIAC gripped the public’s imagination after newspaper reports described it as an “Electronic Brain.” The ENIAC took only 30 seconds to compute trajectories that would have required 40 hours of hand calculations.
The Stored-Program Concept
ENIAC had its share of problems. It was frustrating to use because it wouldn’t run for more than a few minutes without blowing a tube, which caused the system to stop working. Worse, every time a new problem had to be solved, the staff had to enter the new instructions the hard way: by rewiring the entire machine. The solution was the storedprogram concept, an idea that occurred to just about everyone working with electronic computers after World War II. With the stored-program concept, the computer program, as well as data, is stored in the computer’s memory. One key advantage of this technique is that the computer can easily go back to a previous instruction and repeat it. Most of the interesting tasks that today’s computers perform stem from repeating certain actions over and over. But the most important advantage is convenience. You don’t have to rewire the computer to get it to do something different. Without the stored-program concept, computers would have remained tied to specific jobs, such as cranking out ballistics tables. All computers that have been sold commercially have used the storedprogram concept.
Using 17,480 vacuum tubes, ENIAC was a true programmable digital computer that was one thousand times faster than any existing calculator.
History of Computers and the Internet
The Generations of Computer Development
Generation First Second Years 1950s Early 1960s Circuitry Vacuum tubes Transistors Characterized by Difficult to program; used only machine language Easier to program (highlevel languages); could work with business tabulating machines; cheaper Timesharing, minicomputer (SSI, MSI, LSI) Personal computer; graphical user; user interface; LANs; Internet
Mid-1960s to 1970s Mid-1970s to Present
Integrated circuits VLSI and the Microprocessor
THE COMPUTER’S FAMILY TREE
The PC that’s sitting on your desk is, in many respects, a direct descendent of ENIAC-inspired research, including the stored-program concept. Of course, your computer is thousands of times faster and thousands of times less expensive than its room-filling, electricity-guzzling predecessors. When we’re talking about a PC, the “computer” is the microprocessor chip, which is about the size of a postage stamp and consumes less energy than one of the desk lamps in ENIAC’s operating room. How was this amazing transformation achieved? Today’s computers weren’t achieved in a gradual, evolutionary process, but rather by a series of technological leaps, each of which was made possible by major new developments in both hardware and software. To describe the stage-by-stage development of modern computing, computer scientists and historians speak of computer generations. Each generation is characterized by a certain level of technological development. Some treatments of this subject assign precise dates to each generation, but this practice overstates the clarity of the boundary between one generation and the next. Table 1B.1 introduces the four generations of computing technology. In subsequent sections, you’ll learn about each in more detail.
The First Generation (1950s)
Until 1951, electronic computers were the exclusive possessions of scientists, engineers, and the military. No one had tried to create an electronic digital computer for business. And it wasn’t much fun for Eckert and Mauchly, the first to try. When the University of Pennsylvania learned of their plans to transform ENIAC into a commercial product, University officials stated that the university owned the duo’s patent. Eckert and Mauchly resigned to form their own company, the Eckert-Mauchly Computer Company, and landed a government grant to develop their machine. They underestimated the amount of effort involved, however, and would not have delivered the computer if they hadn’t been bailed out by Remington Rand, a maker of electric shavers. With Rand’s financial assistance, Eckert an...