1. Introduction to Computers QUME 185

2. 2 Some objectives  define the term, computer, and discuss four basic computer operations  understand the terms hardware and software  identify principal hardware components and explain and their uses  describe the use and handling of hard disks, other disk types (e.g. CD-ROM) and other storage media (e.g. USB devices)

3. 3 More objectives  understand the difference between system software and application software

4. 4 Definition A computer is an electronic device (or collection of devices), operating under the control of instructions stored in its own memory

5. 5 Capabilities  can accept data (input)  manipulate the data according to specified rules (process)  produce information (output) from the processing, and  store the results for future use

6. 6 Four basic operations: The Information Processing Cycle  Input  Process  Output  Storage

7. 7 Hardware  Hardware refers to the physical components (devices) that make up a computer  This includes peripheral devices as well as internal components

8. 8 Modern computers  Speed  Reliability: (low failure rate)  Accuracy  Storage capacity  Communication: (a connected device)

9. 9 Hardware components

10. 10 Parts of a system Each device is associated with a phase of the information processing cycle

11. 11 Random access memory (RAM)  RAM (Random Access Memory) is the place in a computer where the operating system, application programs, and data in current use are kept so that they can be quickly reached by the computer's processor.  Much faster to access than data stored on hard drive  Data only stays in RAM only while the computer is turned on  1GB is now common

12. 12 Auxiliary storage  Hard disk (Usually internal but can be external)  CD/DVD disk (portable, removable and widely supported)  USB micro drives and similar devices

13. 13 CD-ROMs & DVDs  Metal storage medium that can hold large amounts of data.  CD ~ 650 MB  DVD ~ 17 GB  Removable, portable & universal  CD – ROM ~ read only  CD-R ~ recordable  CD-RW ~ re-writable

14. 14 Software  Software refers to the programs that give instructions to the computer  carries out tasks for users  Programs can be written in a variety of programming languages such as Basic, C++, Java etc.  Two main types of software  system software  application software

15. 15 System software  Programs that control the operation of the computer  This includes the Operating System  Many operating systems: Windows, Macintosh, Linux, Unix  See web page for key operating system functionsweb page

16. 16 System software  Consists of programs to control the operations of computer equipment – especially the operating system (OS).  Instructions in the OS tell the computer how to perform the functions of loading, storing and executing applications software.

17. 17 Application software  Programs that perform specific tasks  There are thousands of different types of application software – for business, pleasure, scientific, educational and many other purposes

18.  Word processing – creating all kinds of documents  Spreadsheet – performing calculations and financial projections  Presentation graphics –slides (like this)  Database – managing and retrieving data 18 More application software These are the main programs we work with in QUME 185

19. 19 File extensions  Each Windows application has a native file format. Textbook, p 23  Format is indicated by a file extension. Examples:  Word:.docx extension (older:.doc)  Excel:.xlsx extension (older:.xls)

20. 20 File extensions can be made hidden or visible using the View tab of the Folder Options dialogue, available under the folder’s Tools menu Extensions

21. 21 Help menu / About …  Help / About … in any software will display information about version number and ownership

22. 22 The Help Menu If you need a quick answer, the Help menu usually provides the information

23. 23 Some ideas to think about  Future of desktop PCs and notebooks (other devices?)  A Few Trends: VOIP Music / movie downloads News on demand ~ mobile devices ~ iPods Podcasting Blogging Social networking ~ FaceBook ~ Wikis ~ Second Life Google Maps / Google Earth Cloud computing Can you think of others?

24. 24 We can end here

25. 25 From data to information  Data: raw facts, figures, and symbols such as numbers, words, images, video and sounds  Information: data that are organized, meaningful and useful  Note: data is strictly speaking the plural of the word, datum

26. 26   Yellow Highlighting indicates some of the key differences

27. 27

28. 28 Bad predictions – hard disk space n 640K ought to be enough for anybody. - Bill Gates, 1981

29. 29 Bad predictions – big iron n Computers in the future may weigh no more than 1.5 tons. -Popular Mechanics, forecasting the relentless march of science, 1949

30. 30 Bad predictions – market size n "I think there is a world market for maybe five computers." Thomas Watson, chairman of IBM, 1943

31. 31 Bad predictions – home computing n There is no reason anyone would want a computer in their home. Ken Olson, president, chairman and founder of Digital Equipment Corp., 1977

32. 32 Bad predictions – the microchip n But what... is it good for? -engineer at the Advanced Computing Systems Division of IBM, 1968, commenting on the microchip

33. 33 Technology as a business driver n Hype n Reality