Unit 1: History of the Computer

1. Unit 1: History of the Computer This lesson summarizes the historical development of computing devices over the past several hundred years.

2. Unit 1 Objectives • I can use and understand basic computer terminology. • I can outline historical developments in computer technology and identify key figures in the history of computers. • I can analyze the impacts of technology on history and society.

3. Did you know that the earliest computers were not machines? • Before the electronic computers of today, we relied on individuals who used mathematics to solve equations. • At that time, computing was thought of as an occupation. • Since then, our understanding of computers has changed and focused on machines.

4. As computer technology has evolved, computers have become an indisputable part of our daily lives. • This lesson introduces you to some of the first forms of computers. It also explains the major historical breakthroughs in computing technology. • By the end of the lesson, you will understand how computing technology evolved into its present form.

5. Early Computers • The earliest computer devices were much different than the ones we use today. • They had no keyboard, mouse, or monitor. They did not even use electricity. • In fact, if you were to see one of these devices today, you would probably not realize you were looking at a computer.

6. Mechanical Computers • Because early computers did not use electricity, they are referred to as mechanical computers. • Mechanical computers rely on parts that must be physically moved in order to perform a task.

7. Mechanical Computers • The earliest and simplest mechanical computer is known as the abacus. • With these basic machines, which are still in use today, beads represent numbers. • People can solve addition and subtraction problems by sliding beads back and forth on a string. The zero position is for all beads to be away from the central bar, as the beads on the left are. The top two beads represent five each, and the bottom beads represent one. The units column has a single 'one' bead and no 'five' beads, so this is one. The tens column has one 'five' bead and two 'one beads, representing 70. The hundreds has a 'five' bead alone, so that is 500. Then there is 3000 and 60,000. So the total number is 63,571.

8. Mechanical Computers • The slide rule is another early computing device. Developed in the 1600s, the slide rule is a mechanical computer on a stick. • It is commonly used to solve multiplication and division problems. Because of its usefulness and convenient size, most high school and college math students carried a slide rule with them to class up through the mid 1970s. • The slide rule was gradually replaced by handheld calculators.

9. Mechanical Computers • Several complex mechanical computers were also developed in the 1600s. • One of these was created by German scientist Wilhelm Schickard. Schickard's computer used gears to add and subtract numbers. It could also multiply and divide. • About 20 years later, French mathematician Blaise Pascal invented a similar device. • However, communities in the 1600s were still largely agrarian and had little use for mechanical computers. As a result, complex mechanical computers were rare and mostly used by scientists.

10. Computers in the Industrial Age • European life began to change in the early 1800s. • As industry spread across the continent, people started leaving their farms to work in factories where goods were produced. • The more technologically advanced a factory was, the more goods it could manufacture and sell for profit. • Recognizing this trend, French inventor Joseph-Marie Jacquard developed a system of punch cards to increase productivity in textile factories.

11. Jacquard’s Loom • When placed into a silk loom, a type of cloth-making device, the punch cards created a type of primitive computer program. • The cards controlled the patterns the loom followed, which ultimately created different types of cloths and designs.

12. Jacquard's invention greatly improved output and reduced human error in the production process. • The invention impressed French leaders, including Napoleon. • But a group of silk weavers feared the computing device would put them out of work, so they destroyed one of Jacquard's first looms. • In the end, the invention was too useful to be ignored. By the time of Jacquard's death in 1834, there were more than 30,000 looms using punch cards.

13. The Analytical Engine • In the 1830s, an English mathematician and scientist named Charles Babbage built upon Jacquard's work. • He invented the Analytical Engine, a machine that could solve complex math problems using punch cards adapted from Jacquard's silk loom. • Unlike Jacquard's silk loom, which required workers to manually insert a single punch card at a time, Babbage's Analytical Engine used a series of punch cards. Once a calculation had been completed, the punch card was fed back into the machine where another punch card used the calculation to complete a different problem. • In this way, the Analytical Engine was the first machine to utilize computer memory.

14. Heading Towards the 20th Century • By the end of the 19th century, punch cards were being utilized to increase efficiency across a variety of platforms. • In 1890, Herman Hollerith's tabulating machine assisted the United States with its 10-year census. The Tabulator used punch cards to automatically count the number of people in the country. • Instead of taking eight years to compile, like the 1880 census, the 1890 census was completed in a single year. • The success of the Tabulator led Hollerith to merge his company with several others. They formed International Business Machines (IBM) in 1924.

15. Practice Questions Answer each question before proceeding to the next slide.

16. How was data (information) entered into Jacquard's silk loom, Babbage's Analytical Engine, and Hollerith's Tabulator?

17. An abacus is primarily used for ______________ , while a slide rule is primarily used for _______________. • Addition and subtraction; multiplication and division • Multiplication and division; addition and subtraction • Simple math; logarithms • Logarithms; simple math

18. What is the biggest difference between the computer you are using and mechanical computers?

19. Practice Answers The information was entered using punch cards. A Mechanical computers do not use electricity. They have moving parts that help perform tasks.

20. Early Electronic Computers • Electricity began to change the lives of people around the world in the early 20th century. • Household appliances such as irons, toasters, and lamps became electrically powered. • In almost all cases, this use of electricity improved the devices and made them more efficient. • It was no surprise when computers began to utilize this new power source as well.

21. Mark I • One of the most notable early electronic computers was the IBM Automatic Sequence Controlled Calculator (ASCC), more commonly known as the Mark I. • Completed in 1944 by Harvard professor Howard Aiken with financial support from IBM, the Mark I used electricity to open and close mechanical switches. • When opened and closed, these switches created a type of Morse code that the machine could understand. • The Mark I was able to calculate problems with numbers up to 23 digits long, a large calculation at the time.

22. Mark I • Despite its unprecedented computing power, the Mark I's capabilities were limited to arithmetic and other math operations. • Making matters worse, it was about 50 feet long and eight feet high and nearly impossible to transport. • Performing maintenance on the computer's 750,000 parts and 500 miles of wire was also challenging.

23. What is Binary Code? • Binary code, the type of computer-based Morse code used by the Mark I, is still used in computers today. • Much like our alphabet conveys information to us through letters, binary codes conveys information to a computer. • In place of letters though, binary code uses just two bits of data: electricity ON and electricity OFF. • To process information, the computer understands each on and off switch as either a 0 or 1. • When eight of these bits of data are pieced together, a computer byte is formed.

24. Each computer byte has its own series of zeros and ones that forms a pattern the computer understands. • These patterns are then processed and turned into the letters, punctuation marks, and numbers we recognize on a computer monitor or other commands related to computer functions. • When computer equipment has the acronyms MB (megabyte) or GB (gigabyte) written on it, it is a reference to binary code. • Megabyte means about 1 million bytes. • A gigabyte is roughly 1 billion bytes. • These acronyms are used to indicate the amount of computer memory or a file's size.

25. ENIAC • One of the most well-known early electronic computers was the Electronic Numerical Integrator and Computer, or the ENIAC. • It was proposed by John Von Mauchly and built by John Presper Eckert, Jr. at the University of Pennsylvania. • It was mainly used by the U.S. military and helped calculate, among other things, the trajectory of artillery shells. • Unlike the Mark I, which used mechanical switches, ENIAC utilized vacuum tubes to transmit signals and information. Similar in appearance and size to light bulbs, vacuum tubes had no moving parts. However, they could still stop and start the flow of electricity much like the switches in the Mark I. a vacuum tube

26. Completed in 1946, ENIAC has been called the first successful general purpose computer, which means it could be programmed to do multiple tasks. • It was able to perform 5,000 math operations per second. • This type of performance meant it was roughly 1,000 times faster than the Mark I. • Like the Mark I, it was massive in size (about 100 feet long and 10 feet tall). • It also contained tens of thousands of parts, including 18,000 vacuum tubes. • In total, the ENIAC cost about $500,000 to produce. Employees monitor ENIAC

27. UNIVAC I • By 1951, Eckert and Mauchly had left the University of Pennsylvania and started their own company. They began work on an upgrade to the ENIAC called the UNIVAC I. This new machine was the first mass-produced computer. • Like the ENIAC, the UNIVAC I used vacuum tubes. • It was sold to and used by a number of U.S. government organizations, including the Census Bureau, the air force, and the army. • It was also used by many large commercial companies.

28. The UNIVAC I is best known for helping CBS, a major television network, accurately predict the results of the 1952 U.S. presidential election before the final results were tallied. • Afterward, other networks scrambled to acquire computer technology to help assist them with predicting election results. • To this day television networks are able to project winners in elections before the polls close because of computers.

29. Development of the Transistor • One of the major problems with the ENIAC, UNIVAC I, and many other early electronic computers was their heavy dependence on vacuum tubes. • Although they were an improvement over mechanical switches, vacuum tubes required a lot of energy and produced a significant amount of heat. This often required that they be placed in an air conditioned room. • The tubes were quick to wear down and in constant need of replacement. With 18,000 tubes in the ENIAC alone, maintenance became an ordeal.

30. In 1947, three American physicists invented the transistor, a replacement for the vacuum tube that took about a decade to gain widespread use. • Although transistors performed the same functions as vacuum tubes, they used less energy, produced less heat, and were more reliable. They also worked faster, which allowed computers to have more capabilities. • The transistor is considered one the greatest developments in computer design and is widely regarded as one of the most important inventions of the 20th century. In fact, they are still included in most electronic devices built today. • The computers that are used today have millions, and sometimes billions, of transistors within them. Trillions of transistors are manufactured around the world every year. • Today’s transistors are thousands of times smaller than the original. Replica of the first transistor

31. Practice Questions Answer each question before proceeding to the next slide.

32. What was the first successful general computer? • Mark I • ENIAC • UNIVAC I • Tabulator I

33. How many bytes are in a gigabyte? • 1 • 1,000 • 1 million • 1 billion

34. Why are transistors better than vacuum tubes?

35. Practice Answers B. ENIAC D. 1 billion Transistors are faster, use less energy, produce less heat, and are more reliable than vacuum tubes.

36. Integrated Circuits • Developed by American scientists in the 1960s, integrated circuits allowed dozens of transistors to fit into a single piece of silicon, a semiconductor that allowed for easy data transfer. • More commonly known as chips or microchips, integrated circuits looked like small electronic caterpillars. • Large numbers of transistors can be placed within a few integrated circuits like those pictured.

37. Microprocessors • As scientists continued to develop integrated circuits, they found ways to fit even more transistors into smaller spaces. • Actually, the number of transistors within integrated circuits has roughly doubled every two years since the 1960s. • Eventually this led to the development of microprocessors. • Microprocessors are integrated circuits that are capable of processing all of the information for a computer. • This information ranges from individual applications, such as Web browsers and games, to operating systems, a type of software that tells the computer how to function. They also process minor computer activities such as typing and clicking the mouse. • Over the past few decades, microprocessors have become faster and more powerful, helping computers to continually expand their capabilities.

38. Think About It! In 1969, the National Aeronautics and Space Administration (NASA), the United States' space exploration agency, launched Apollo 11, a mission that landed humans on the moon for the first time. This achievement would not have been possible without computer technology. Did you know though that the computer onboard that guided the Apollo 11 had less computing power than many cell phones today? What types of computing activities do you use your cell phone for?

39. Personal Computers • Apart from the abacus and slide rule, most computers in the early 1970s were owned by governments or other large institutions. • Few individuals or small businesses could afford computers at the time. • That began to change in 1975 when the Altair 8800 was released by Micro Instrumentation Telemetry Systems.

40. Altair 8800 • The Altair 8800 is considered the world's first personal computer because the average person could afford and use it. • It cost just $400 when it was released. However, it had no keyboard or monitor, and it was difficult to use. • Users had to create their own programs for the Altair 8800 using switches on the front cover. Red lights on the front cover would then convey information back to them.

41. Despite its shortcomings, the Altair 8800's relatively low cost allowed thousands of users to purchase the device and experiment with improving its capabilities. As a result, many individuals began careers in the computing field. • Two such individuals were Bill Gates and Paul Allen, cofounders of the Microsoft Corporation, whose first product was a programming language interpreter for the Altair in 1975. • About five years later, they began work on an operating system for the IBM Personal Computer called MS-DOS.

42. MS-DOS • MS-DOS quickly became the industry standard for personal computers. • As computer technology improved, the need for the MS-DOS operating system increased with the demand for personal computers. • MS-DOS used a command-based interface which required users to manually enter commands for a program to run. • However, many people found the command-based operating system difficult to use.

43. Apple I • One of Microsoft's main competitors over the years has been Apple Computer, Inc. (now known as Apple Inc.). • Established in 1976 by Steve Jobs and Stephen Wozniak, the company's first product was called the Apple I. • The Apple I was an early personal computer much like the Altair 8800.

44. Graphical User Interfaces • Over the years, Apple has released a series of computers and operating systems known for their easy-to-use GUIs. • Microsoft Windows is an operating system that uses Graphical User Interface (GUI). • GUIs allow users to interact with their computers using graphics, text, and icons displayed on a monitor. • Since they are much easier to use than command-based systems, GUIs gained widespread use.

45. Microsoft vs. Apple • Microsoft's dominance continued into the 1990s with the launches of Microsoft Windows and Office. • Microsoft Office is a suite of products used for word processing, spreadsheet creation, e-mail, and other publishing functions. • However, Apple has also expanded into other computer-related products, including the popular iPod musical device and the iPhone. • Although the vast majority of personal computers in the world use Microsoft Windows as their operating system, the Apple operating system has seen its market share increase in the 21st century.

46. Unit Review • Computing power has increased dramatically from the mechanical processes of the abacus and the punch cards used by Jacquard to the microprocessors and electronic computers of today. • Computers have drastically shaped the way the world works and how people interact – especially within the past century and they continue to evolve. • Everything from talking on our cell phones to landing on the moon has been made possible because of this technology.

47. As you continue to learn about computers throughout the rest of this course, take notice of the different types of technology around you. • Ask yourself, "How would my life be different without cell phones, iPods, iPhones, smart phones, personal computers, and smart boards?" • Although you might take it for granted, much of the computer technology that you enjoy today was either not around or not affordable when your parents or grandparents were your age.

48. Practice Questions Answer each question before proceeding to the next slide.

49. Which of the following is a mechanical computer? • Abacus • UNIVAC I • ALTAIR 8800 • ENIAC

50. Over the past several decades, • The number of punch cards within integrated circuits has dramatically increased. • The number of punch cards within integrated circuits has dramatically decreased. • The number of transistors within integrated circuits has dramatically increased. • The number of transistors with integrated circuits has dramatically decreased.