2. Zaipul Anwar bin Zainudin Institute of Product Design & Manufacturing Universiti Kuala Lumpur Session 3

3. Objectives Describe the three fundamental characteristics of computers Describe at least four areas of society in which computers are used Identify the basic components of a computer system: input, processing, output, and storage List some common input, output, and storage media Distinguish data from information Describe the significance of networking Explain the significance of the Internet Explain the various classifications of computers

4. What is a software? - The instructions needed to direct the computer to complete specific tasks. - Software can be categorized into two types :- Operating System and Its Function

5. Application Software - program that tells a computer how to produce information - examples of application software : Business, scientific, educational programs and etc. System Software - program controlling the actual operations of the computer equipments - the operating system tells computer how to perform functions such as load, store, execute application program, transfer data between I/O devices and main memory Operating System and Its Function – cont.

6. Definition of OS :- A set of programs that control and supervise a computer system’s hardware Purposes of OS :- To manage the hardware for efficient utilization of computer resources To interface between a user/an application program with the hardware Operating System and Its Function – cont.

7. OS is made up of 2 programs; Operating System and Its Function – cont. Control Program Service Program

8. 1.Control program- three main functions Operating System and Its Function – cont. Resource allocationallocate processor time, primary storage, input and output devices Job managementto monitor, schedule and control programs for its efficient processing Data management-managing access to data for input of information to printers, disks/displays - all hardware components activities are controlled by the supervisor program

9. 2. Service programs - provides services to the user/programmer - services include language-translator programs and utility programs - language-translator program converts instructions from English-like language to machine-language to be executed by the computer - utility program performs loading, saving, copying, keeping track of files stored on a disk, preparing a formatted disk Operating System and Its Function – cont.

10. Language Translator Utility Program Other Services Data Mgmt. Job Mgmt. Resource Allocation Supervisor Operating System and Its Function – cont.

11. What an Operating System does? 1.Checks the functionality of the computer’s hardware. It generates an error message (by messages or beeps) if any components are found faulty. 2.Then the OS control programs will load the supervisor program into the computer’s memory – booting 3.Once the supervisor control program in memory, the system displays the prompt sign (C:\>), indicating that it is ready to work

12. MS-DOS DOS is the supervisor program of the computer It does all the followings Interface to peripherals – How to interpret input, how to process data, and how to produce output Application launcher – Most programming software, games etc. use DOS prompt to run application Utility provider – Manage disks and files, prepare disks for storage, copy files to a disk, to move or rename files, and to delete files

13. MS-DOS – cont. Using DOS prompt to get command from user Examples for DOS operation DOS version/prompt type Modify date/time File and directory contents Clearing a DOS screen Going to subdirectory and back to root directory Searching for specific files Copy files from A drive / C drive

14. TYPES OF OS Microsoft Windows (98, 2000, XP, Vista) Mac OS (X) Linux OS (Hundreds of even thousands of distros ex: Red Hat, Ubuntu, Mandrake etc. Visit http://distrowatch.com/ http://distrowatch.com/ for listing of Linux OS) Unix OS etc.

15. TYPES OF BROWSERS Mozilla Firefox Internet Explorer Opera Safari Konqueror Flock Firefox is gaining Popularity over IE Flock

16. Low and High Level Languages Programming Language - a set of written symbols that instruct the computer hardware to perform certain tasks - can be categorized as Low level Language and High Level Language Low Level Language -Language that has the tendency towards specific, delicate machine syntax -Machine Language and Assembly Language

17. - consists of entirely 1’s and 0’s that only the computer understands - depends on different, specific hardware designs - it executes very fast, but is time consuming and difficult to understand - only programmer who has the knowledge of the computer architecture is able to understand the language Low and High Level Languages – cont. Low Level Language – cont. Machine Language

18. -also considered as Low Level Language because it still needs specific knowledge of hardware -it differs from machine language because of it uses mnemonic in spite of 1’s and 0’s to represent the operation codes -mnemonic code is an alphabetic abbreviation that is easy to remember -it produce programs very efficient, less storage usage and the execution is much faster Low Level Language – cont. Assembly Language Low and High Level Languages – cont.

19. - instructions resemble human language and mathematical notation - no detail knowledge of computer hardware and internal operation of a computer - easier to learn because of the English-like language rather than understanding machine codes and instructions - E.g. FORTRAN, COBOL, BASIC, Pascal, C/C++ Low and High Level Languages – cont. High Level Language

20. Assembler, Compiler and Interpreter Assembler Compiler/Interpreter (Source code) (Object code)

21. - the source code will remain unchanged after the conversion but can be updated and changed, then compiled again - after it is compiled, then the object code can be executed -example of HLL program uses compiler is the C and C++ - the interpreter will translate a program one line at a time, executing each line of the program after it is translated - if an error should occur during execution, the error must be rectified or solved before it can proceed to the next line - example of HLL program uses interpreter is the BASIC Assembler, Compiler and Interpreter – cont. Compiler Interpreter

22. Importance of Backup – cont. Data is exposed to several threats.

23. Uninterruptible Power Supply (UPS) How does UPS works? - it is connected in series with the computer system - when power is interrupted, this result the UPS to function as a backup supply of power to the computer system - depends on the type of UPS, it will operate in 20 minutes or more - it is advisable to backup important data within the time limit to prevent any lost of data Importance of Backup – cont.

24. Components of UPS - one rectifier (charger) to convert AC to DC and to fully charge the battery - one battery to supply DC power to the inverter and the supported time are based on the number and size of batteries - one inverter to convert DC to AC - one static bypass switch to control the load from/to the power source to/from the battery and allows certain load to transfer tolerances needed by the computer and its peripherals Importance of Backup – cont.

25. The Computer Virus Crisis The elements of a computer virus : 1. A set of instructions- a program being made to disrupt or interfere other programs 2. Deliberately created- purposely created by humans or by itself 3. Actively propagates- reproducing itself 4. Infects other programs- contaminate or polluting different types of programs 5. Able to do harm- can cause damage to others 6. Able to evolve- developing, growing and changing in programs or systems

26. The Computer Virus Crisis – cont. What are the damages of the virus to a computer system : 1. Creates garbage in your computer system that takes up space in the memory and into your diskettes 2. Messing up files in their normal standard and altering some of the files 3. Messing up the FAT (File Allocation Table) which contains information of where are the other data's stored on your disk 4. Messing up the boot sector that can restrict your computer from being able to execute at all

27. The Computer Virus Crisis– cont. Types of anti-virus software The Computer Virus Industry Association (CVIA) in the USA has developed three basic categories of anti-virus software. To prevent initial infection To detect infection To identify and remove viruses

28. COMPUTER NETWORKING Network : Computers connected together to communicate among themselves. Resource Sharing File Sharing Communication PCs’ Administration and Security

29. - Computer network technology can be classified by the distance the network technology is designed to span - There are three types of networking : Local Area Network (LAN) Metropolitan Area Network (MAN) Wide Area Network (WAN) COMPUTER NETWORKING –cont.

30. Local Area Network (LAN) - Relatively small refers to the transmission media and computer hardware - The area is not exceeding 10 KM - It only uses one type of transmission medium - It share resources within building or campus COMPUTER NETWORKING –cont.

31. Metropolitan Area Network (MAN) - The network is larger compared to LAN - The area covers a city of 10 to 100KM - It requires efficient hardware and transmission media to cover these areas COMPUTER NETWORKING –cont.

32. Wide Area Network (WAN) - The network is larger than MAN and LAN - It interconnect LAN of opposite sides of country or around the world - It covers huge geographical area in the world COMPUTER NETWORKING –cont.

33. Local Area Network RouterMultiplexer Modem Front end Processor Host Computer

34. LAN COMPONENTS Every LAN is made up of a standard set of components:

35. Topology: The physical connection among computers within a network - the topology is the configuration of the hardware and shows which pairs of nodes can communicate -there are three common types of topologies :- LAN TOPOLOGIES Star topology Ring topology Bus topology

36. Star Ring Bus

37. LAN PROTOCOLS Protocol : A set of rules to access the network to send data. Two common LAN protocols

38. TRANSMISSION MEDIA Transmission Media : The physical medium used for transmission. Types of TM Coaxial Cable Twisted Pair Cable Fiber Optic Cable Satellite Transmission Microwave Transmission

39. TRANSMISSION MEDIA - Twisted Pair Cable Colour-coded insulation Jacket Copper wire conductor

40. Inner conductor Insulation Outer plastic covering TRANSMISSION MEDIA – Coaxial Cable

41. TRANSMISSION MEDIA – Fiber Optic Cable Optical fiber Protective outer sheath Glass covering Strength wires

42. TRANSMISSION MEDIA – Microwave

43. TRANSMISSION MEDIA – Satellite

44. ANY QUESTIONS?