Introduction to Computers

1. Introduction to Computers

2. What is a computer? • A computer is a electromechanical device which can be programmed to change (process) information from one form to another. • Do exactly as they are told. • Digital devices: Understand only two different states (OFF and ON)

3. First Generation – Vacuum Tubes • 1930’s – Vacuum tubes were used as electronic circuits or electronic switches.

4. First Generation – Vacuum Tubes • First electronic digital computer built by Konrad Zuse, who developed his first machine, the Z1, in his parents' living room in Berlin in 1938. • Another early digital computer was built by Dr. John Atanasoff and his assistant Clifford Berry, known as the ABC (Atanasoff Berry Computer) built at Iowa State University during 1937-42.

5. 1946 - ENIAC • First large-scale electronic digital computer was ENIAC (Electronic Numerical Integrator and Calculator) • 30 feet long, 8 feet wide, and 8 feet high • 3 additions every second, (incredibly slow by today’s standards).

6. 1946 - ENIAC • Grace Hopper, one of the first programmers on the ENIAC and the developer of the programming language COBOL, says, “It was the first machine that assisted the power of man’s brain instead of the strength of his arm.” • ENIAC was developed long before the days of silicon chips or microchips, even before the transistor was invented. • Like ABC, ENIAC was made up of vacuum tubes, over 18,000 of them!

7. 1951- UNIVAC 1 • 1951 the first commercially available computer was developed, the UNIVAC I (UNIVersal Automatic Computer) using vacuum tubes • 3,000 additions every second. • In 5 years we were going a thousand times faster.

8. 1951- UNIVAC 1 • Rear Admiral Grace Hopper, USN, with other programmers. • Photo taken, August 13, 1957

9. Second Generation – Transistors • 1947 - Walter Brittain and Willaim Shockley invented the transistor at Bell Laboratories • Replaced the vacuum tube as an electronic switch

10. 1954 - TRADIC • TRADIC (TRAnsistorized Airborne DIgital Computer) • 800 transistors. • First computer system to completely use transistors • First computer to be successfully operated in an aircraft, an environment which was hostile to previous computer systems.

11. Second Generation - Transistors Transistors were: • Smaller • Faster • More reliable • Less expensive

12. Third Generation – Integrated Circuits • 1959, Jack Kirby and Robert Noyce at Fairfield Semiconductor (who was later to become the cofounder of Intel Corp.) developed the first integrated circuit (silicon chip or microchip). • An integrated circuit (IC) is a system of interrelated circuits packaged together on a single sliver of silicon. • It is a way of placing multiple (millions) transistor devices into as single, smaller device, the “microchip.”

13. 1960 – IBM 360 • 1 addition every billionth of a second (nanosecond), or a billion additions every second

14. Third Generation – Integrated Circuits ICs, chips, were: • Smaller • Faster • More reliable • Less expensive

15. Fourth Generation - Microprocessor • A microprocessor is a Central Processing Unit (CPU) on a single chip. • 1971, Intel Corp. introduced the first microprocessor chip. • Intel 4004 • 108 kHz and contained (equivalent of) 2300 transistors

16. IBM used it for calculators not computers • Busicom desk-top printing calculator, the world’s first commercial product to use a microprocessor. • Used the Intel 4004 CPU.

17. 1975 - Altair 8800 • Ed Roberts and the first microcomputer or personal computer (for the consumer) the Altair 8800

18. MITS Altair 8800 • Microcomputer - a computer which has a microprocessor. • Used the Intel 8080 Microprocessor

19. Microprocessors

20. 1972 - Xerox Alto • Xerox Alto – first microcomputer. • Developed at Xerox PARC (Palo Alto Research Center) • Not for consumer market. • 1981 – Xerox Star • Xerox executives “just didn’t get it”.

21. 1976 - Apple I • Steve Jobs and Steve Wozniak developed the Apple I microcomputer in their basement. • Though it was a flop, its successor became the first popular home computer

22. 1977 – Apple II

23. Others from 1977 - 1981 Kaypro Commodore PET 2001 Osbourne Tandy TRS-80

24. Others from 1977 - 1981 Texas Instruments Atari IMSAI Timex Sinclair

25. 1981 – IBM PC • What everyone was waiting for, or fearing… • “Open Architecture” and IBM

26. 1984 – Apple Macintosh

27. 1985 – Microsoft Windows 1.0

28. 1987 – IBM PS2 and OS2 • Closed architecture (similar to Apple) • Never made it.

29. Trends from 1990 to today… • Microsoft continues to develop and improve Windows with latest version Windows XP and working on “Longhorn” • LINUX operating system, an open source version of UNIX, is taking on MS Windows and gaining in popularity • IBM has rebounded and continues to make personal computers, laptops, mainframes and minicomputers • Apple continues to be a major player in personal computers, especially for the “creative market”, iPods, etc. • Apple switching from IBM PowerPC CPU to Intel • DELL, Compaq, Gateway, HP, IBM • Internet, networking, convergence

30. Trends from 1990 to today… • Faster • Smaller • More reliable • Less expensive • Easier to use

31. Traditional Types of Computers • General purpose computers • Mainframe • Minicomputer • Microcomputer (Personal Computer)

32. Traditional Types of Computers • First computers, introduced in 1950s • Used by large businesses • Typically supported 100 to 500 users • Very expensive • Used for very large processing tasks • Mainframe Computers

33. Traditional Types of Computers • Typically supported 10 to 100 users • Smaller and less expensive than mainframes • The real difference is relative in terms of price, power, marketing. • Minicomputers

34. Traditional Types of Computers • Small, self-contained computers with their own CPUs • Used by home and business users • Uses a microprocessor, a CPU (Central Processing Unit) on a single chip. • Microcomputers (Personal Computer or PC)

35. Portable Computer • What are these types of portable computers (a type of personal computer)? • Desktop computers • Laptop computers • Personal Digital Assistants (PDAs)

36. Networked computer • Networked computer = Computers connected to other computers or peripheral devices (printers, etc.) to share information. • What is the difference between these two networked devices? Dumb terminal • No CPU (uses server’s) • No Operating system (uses server’s) • Input and Output only Intelligent terminal (computer)

37. Embedded Computers • Embedded computers – Computers found in consumer goods in order to enhance their function.

38. Special Purpose Computers • Special purpose or dedicated computers – A device with a specific purpose such as game system or information kiosk.

39. Hardware versus Software • Hardware = The physical components that make up a computer system. • More in a moment… • Much more on all of these items in later presentations!

40. Hardware versus Software • Software = The programs (instructions) that tell the computer what to do. • System Software • Application Software • Stored on a storage media such as hard disk, CD-ROM, floppy disk, tape, etc. • More later…

41. Hardware Components • This is just an overview, more later…

42. Computers, throw away technology? • When first developed digital computers were as large as a room and cost more than most large business could afford. • Today systems costs have dropped to the level where they are considered throw-away technology

43. Computers, throw away technology? • Computer users fall roughly into two categories: • Home Use • Business Use • Home users want a system that can plug in and use • Internet (Wireless) Most home users do not know how to set up a computer system, and do not want to bother upgrading a system • E-Mail • Games • Learning (tutorials)

44. Computers, throw away technology? • Business today rely on computers for at least some of their daily functions • They view computers as a tool that helps their employees become more productive • The cost of the computer is minor compared to the value it offers a company

45. System Safety Danger do not open there are no user serviceable parts inside. Refer to qualified service technician.

46. No exposed lethal voltage inside a PC • Power Supply is completely enclosed in a sealed unit System Safety • Some cases are stamped out of sheet metal and have sharp edges

47. Static Electricity can cause serious damage to PCs • Facts about static electricity System Safety - It takes approximately 3000 volts before a person can feel the effects - Walking across a carpet can generate as much as 35,000 volts - Walking on vinyl tile can generate 14,500 volts - It takes approximately 30-50 volts to damage components

48. System Safety • Another major concern with computers is the heat generated inside the case • Never place a computer against a wall with no air circulation • Remove dust from the inside of a system periodically • Route wires out of the way so airflow is not restricted inside

49. Timeline of Computer History http://www.computerhistory.org http://www.computerhistory.org/timeline/?category=cmptr