Introduction to Computers. Computer Science Department 101COMP حال - 3 للكليات العلمية

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1 Introduction to Computers Computer Science Department 101COMP حال - 3 للكليات العلمية )الطب, الهندسة, الحاسب, العلوم, ادارة األعمال, اللغة االنجليزية( 1

2 1.1 What is Computer? Computer is a programmable, electronic device that accepts data as input, performs processing on that data, and give outputs and stores the results. 2

3 What does a Computer Do? Computers can perform four general operations: Input : Entering the Data Processing : Operation on that data Output : Giving the result on display Storage : Save the data 3

4 1.2 What is Hardware? Hardware is the physical parts of a computer system. Examples: Keyboard Mouse Monitor Printer 4

5 Examples of Hardware Monitor (output) Speaker (output) System unit Printer (output) (processor, memory ) Storage devices Scanner (input) Keyboard (input) Mouse (input) (CD-RW, Floppy, Hard disk, zip, ) 5

6 1.3 What is Software Software is the instructions, also called computer programs, that tell a computer what it should do. 6

7 Types of Software Software The Instruction also called computer program, which tell computer what to do. System Software The Program that allow a computer to operate collectively. All Operating system Windows, XP, Vista Linux, Unix Application Software The Program design to perform specific task. MS Office Photoshop Internet Explorer 7

8 1.3.1 System Software The programs that allow a computer to operate collectively are know as system software. Examples: All operating systems. Windows 7, Vista, XP LINUX, UNIX 8

9 1.3.2 Application Software Application software consists of programs designed to allow people to perform specific task. Examples: MS Office (Word, Excel, Access..) Photoshop Internet explorer 9

10 1.4. Types of Computer Users End Users A person who uses the computer to obtain information. Programmer A person whose job is to write, maintain, and test computer programs. 10

11 1.5 Different types of computers Six basic categories of computers Embedded computers Mobile devices Personal computers Midrange servers Mainframe computers Super computers 11

12 1.5.1 Embedded Computers A tiny computer embedded or fixed into a product and designed to perform specific tasks. Examples: Washing machine Microwave Televisions Cars 12

13 1.5.2 Mobile Devices A very small device with some type of Internet capability. Examples: Smart phones Smart watches Handheld gaming devices Portable digital media players 13

14 1.5.3 Personal Computer A computer system designed to be used by one person at a time. Examples: Desktop Pcs Portable computers 14

15 Desktop PC 15

16 Portable Computers 16

17 1.5.4 Midrange Server A medium-sized computer used to host programs and data for a small network. Example: Small Office. 17

18 1.5.5 Mainframe Computer A powerful computer used by several large organizations to manage large amounts of data. Examples: Hospitals. Universities. Banks. Government offices 18

19 1.5.6 Supercomputer Super computer is the fastest, most expensive, most powerful type of computer. Examples: Satellites Weather forecast Oil exploration Scientific research 19

20 Question & Answers What is Computer? What Computer Operations? What is Hardware & Examples? What is Software? Types of Software & Examples? Types of Computer User? Types of Computers? 20

21 2.1 Data Types Data Text Number Image Audio Video Multimedia: The information that contains text, number, images, audio, and video. 21

22 2.2 Data inside the computers Bit : A bit is the smallest unit of data that can be stored in a computer. It is either 1 or 0. Bit Pattern : A string or group of bits is called bit pattern. Example: Byte : A group of 8 bits is called Byte. Example:

23 Data Storage Unit 1 Byte = 8 Bits KB (Kilobyte) = 1024 Bytes MB (Megabyte) = 1 Million Bytes GB (Gigabyte) = 1 Billion Bytes TB (Terabyte) = 1 Trillion Bytes 23

24 2.4 Representing Data Text: A piece of Text is sequence of symbols. Text Representation: 1. ASCII(American Standard Code for Information Interchange): It used 7 bit and has 128 symbols. 2. Extended ASCII: It used 8 bit and has 128 symbols. 3. EBCDIC (Extended Binary Code for Decimal Interchange Code): It used 8 bit and has 256 symbols. 4. Unicode: It used 16 bit and has 65,000 symbols. 5. ISO (International Standard Organization) : It used 32 bit and has 4 Billion symbols 24

25 Text Representation Text Bits Symbols ASCII American Standard Code for Information Interchange Extended ASCII EBCDIC Extended Binary Code for Decimal Interchange Code Unicode 16 65,536 ISO International Standard Organization 32 4 Billion 25

26 2.3.2 Numbers Numbers are represented using the binary system in the computer. A sequence of 0 and 1 represents a number. 26

27 2.3.3 Image Images are represented in a computer by one of two methods. Image Bitmap Graphic Vector Graphic 27

28 Types of Image: 1. Bitmap Graphic : An image is divided into a matrix of pixels, each color pixel is represented its binary code. 2. Vector Graphic : An image is decomposed into a combination of curves and lines, it is represented by a mathematical formula. 28

29 2.4.5 Audio & Video Audio: The analog signal is sampled, the sample are quantized & quantized value are change to binary code. Sample means measuring the value of signal at equal intervals Quantization means assigning a value to a sample Video: Video are set of sequential images called Frames. 29

30 3. Number systems Number system is a way of representing number. Examples: 1. Binary number 2. Decimal number 3. Octal number 4. Hexadecimal number 30

31 3.1 Binary number Binary number represents all numbers using just 2 symbols (0 and 1) Examples: 0 and 1 31

32 3.2 Decimal number Decimal number represents all numbers using 10 symbols (0-9) Examples:

33 3.3 Octal number Octal number is based on 8 symbols and represented in 3 bit pattern. Examples: : Octal Bit Pattern Octal Bit Pattern

34 3.4 Hexadecimal number Hexadecimal number is based on 16 symbols and represented in 4 bit pattern. Examples: A B C D E F Hexadecimal. Bit Pattern Hexadecimal. Bit Pattern A B C D E F

35 Number System Number System Symbols Example Binary Number 2 0 & 1 Decimal Number 10 0,1,2,3,4,5,6,7,8,9 Octal Number 8 0,1,2,3,4,5,6,7 Hexa Decimal Number 16 0,1,2,3,4,5,6,7,8,9, A,B,C,D,E,F 35

36 4. Conversion Decimal number to Binary number Binary number to Decimal number 36

37 4.1 Decimal to Binary conversion Question : Convert Decimal number 35 to Binary number Question : (35) 10 = ( ) 2 Examples: Answer : (35) 10 = ( ) 2 37

38 4.1 Exercises 1 Question : Convert Decimal number 55 to Binary number Question : (55) 10 = ( ) 2 Examples: Answer : (55) 10 = ( ) 2 38

39 4.1 Exercises 2 Question : Convert Decimal number 49 to Binary number Question : (49) 10 = ( ) 2 Examples: Answer : (49) 10 = ( ) 2 39

40 4.2 Binary to Decimal conversion Question : Convert Binary number Decimal number Question : (100011) = ( ) 2 10 Examples: Binary Number x x x x x x Position value = 35 Answer : (100011) = ( 35 )

41 4.2 Exercise Question : Convert Binary number Decimal number Question : (110001) = ( ) 2 10 Examples: Binary Number x x x x x x Position value = 49 Answer : (110001) = ( 49 )

42 5. Types of Memory RAM (Random Access Memory ) SRAM (Static Random Access Memory) DRAM (Dynamic Random Access Memory) ROM (Read Only Memory) PROM (Programmable Read Only Memory) EPROM (Erasable Programmable Read Only Memory) 42

43 Memory Chart Memory RAM It is Volatile memory Information Delete if Computer Power OFF ROM It is Non-Volatile memory Information store permanently SRAM DRAM PROM EPROM It uses Flip-Flop Gate to hold Data. It is Fast It is Expensive It uses Capacitors to hold Data. It is Slow It is Cheaper It s a memory chip Where Program written once cannot be change. It remain Forever. It s a special PROM where Program can be change by Ultra violet light. It can be Re-program 43

44 5.1 RAM (Ramdom Access Memory) RAM is a volatile memory means the information is erased or deleted, if the computer is powered down or Off. 44

45 Types of RAM: SRAM (Static Ramdom Access Memory) It s uses the flip flop gates (a gate with two states: 0 and 1) to hold data. SRAM is fast but expensive. DRAM (Dynamic Ramdom Access Memory) It s uses capacitors. If capacitor charged, the state is 1, else 0 for holding data. DRAM is slow but cheaper. 45

46 5.4 ROM (Read Only Memory) ROM is a non-volatile memory in which data or programs have been permanently stored. 46

47 5.5 Types of ROM PROM(Programmable Read Only Memory): PROM is a memory chip on which data can be written only once, it remains there forever. EPROM(Erasable Programmable Read Only Memory): EPROM is a special type of PROM that can erased data by exposing it to ultraviolet light and it can be re-programmed. 47

48 6. Secondary Storage Devices Types of Storage Devices: 1. Floppy Disk 2. Hard Disk 3. Optical Disc a) CD Compact Disc b) DVD Digital Versatile Disc 4. Flash Memory System a) Flash Memory Card b) USB Flash Drive 48

49 6.1 Floppy Disk Floppy disk is a low-capacity storage removable disk made of plastic for saving up to 3.5 MB. 49

50 6.2 Hard Disk Hard Disk is a high-capacity storage device that consists of one or more metal magnetic disks permanently seal in it drive. 50

51 6.3 Optical Disc & its types Optical disc is a medium-capacity of storage disc that read and write by using a Laser beam. 1) CD (Compact Disc) : CD is an optical disc with a typical storage capacity of 650 MB. 2) DVD (Digital Versatile Disc) : DVD is an optical disc with a typical storage capacity of 4.7 GB. 51

52 6.4 Flash Memory Systems Flash memory system is a storage system that uses flash memory media. 52

53 6.5 Flash Memory Cards Flash memory cards is a small, rectangular shape storage device that uses flash memory media. 53

54 6.6 USB Flash Drives USB (Universal Serial Bus) is a small storage device that plugs into computer USB slot and contains flash memory media. 54

55 6. Secondary Storage Devices Storage Device Capacity Range or Size Floppy Disk Low 3.5 MB Hard Disk High 250 GB to 1 Tera Bytes CD Medium 650 MB DVD Medium 4.7GB Flash Memory Card High 256 MB to 64 GB USB Flash Drive High 256 MB to 64 GB 55

56 7. Input Devices Keyboard Mouse Electronic Pen Scanners Readers Touch Screen 56

57 7.1 Keyboard Keyboard is an input device containing numerous keys that can be used to input letters, numbers, and other symbols. 57

58 7.2 Mouse Mouse is a common pointing input device that user slides on a flat surface. 58

59 7.3 Electronic Pen Electronic pen is an input device that is used to write electronically on the display screen. 59

60 7.4 Scanners Scanner is an input device that reads text and graphics and transfers them to a computer in digital form. Examples : Flatbed Scanners Handheld Scanners 60

61 7.5 Readers Readers are input device that can read different types of code and marks. 61

62 7.5.1 Types of Readers 1. Barcode readers: It is an input device that reads barcode documents. 2. RFID (Radio Frequency Identification) 3. OMR (Optical Mark Reader) 4. OCR (Optical Character Recognition) 5. MICR (Magnetic Ink Character Recognition) 6. Biometric readers 62

63 Types of Readers 2. Radio Frequency Identification (RFID) Readers: A technology used to store and transmit data located in RFID tags. 3. OMR (Optical Mark Reader):- It is input device that read data from special forms for score or tally exams marks result. 4. OCR (Optical Character Recognition):-It is an input device that recognize handwritten or typed characters. 5. MICR (Magnetic Ink Character Recognition):- It is a technology used primarily by the banking industry to for checking process. 6. Biometric Reader:- It is an input device that read biometric data such as (Fingerprint, Hand or face geometry, voice or signature etc..) 63

64 7.6 Touch Screen Touch screen is an input device with the display screen that is touched with the finger to issue commands. 64

65 8.1 Output Devices Display Device: An output device that contains a viewing screen. Types of Display Devices: Monitor: It is an output device for a desktop or Personal Computer. Display Screen: It is an display device built into a notebook, handled PC, Laptop or other devices. 65

66 Display Device Characteristics Pixel: The smallest colorable area on the display device. Color vs. Monochrome Displays: Monochrome Display: It display each pixel in one of the 2 color that is Black or White. Color Display: It display each pixel in combination of 3 color that is Red, Green & Blue (RGB). CRT Monitor vs. Flat Panel: CRT Monitor: (Cathode Ray Tube): A display device that uses electronic gun & Cathode tube for displaying the image. Flat Panel: A Display device that uses electronically charged chemical or gases for displaying the image. 66

67 Display Device Characteristics Types of Flat Panel: 1. LCD (Liquid Crystal Display): A flat panel display device that uses Charged Liquid Crystal to display image. 2. OLED (Organic Light Emission Diode): A flat panel display device that uses emissive organic material to display brighter & Sharper image. 3. Plasma: A flat panel display device that uses layer of gases to display image. Projector: A display device that projects all computer data, output on a wall or projector screen. Screen Resolution: The number of pixel displayed in inch is called Screen Resolution. 67

68 Printers: It is an output device that produces output on paper Types of Printers: Printer Name Laser printer Ink-jet printer Photo printer Barcode printer Portable Printer Plotter Definition It uses toner powder to print image on paper. It spray ink to produce image on paper. It print digital photos. It print barcode documents. It is small hand held printer to carry out for printing. It prints large documents such as Blue print & Maps. 3D Printer It print three dimensional image for prototype. 68

69 69

70 Printers Characteristics: Printing Technology: Impact Printer: A printer that actually strikes or touch the paper to transfer ink to produce image. Example: Dot Matrix Printer Non Impact Printer: A printer usually produce high quality image without touching or striking the paper. Example: Laser Printer & Ink Jet Printer Color vs Black & White Printer: Color Printer: It uses blue, red & yellow color ink to produce color image. It is Expensive. Black & White Printer: It uses only Black color ink to produce image. It is cheap. 70

71 Printers Characteristics: Personal & Network Printer: Personal Printer: The printer that is uses by one computer for printing. Network Printer: The printer that uses or share by number of computers for printing. Print Resolution: The number of dots per inch (dpi) is called Print Resolution. Print Speed: It measured by pages per minutes (ppm). Connection Options: Printers may be connected to LPT1 port, USB or Wi-Fi. 71

72 Audio Output: Audio Output: It is the output from of voice or music. Different types of Audio Output Device: Speaker: It is an Output devices that produce sound. Headphone: A personal audio output device used by individual to hear sound, it has built in microphone called headsets. Communication between CPU and Input/Output devices 72

73 What are the technology of connecting CPU and Input/Output ( I/O ) Units? USB (Universal Serial Bus ) SCSI (Single Computer Serial Input ) Fire wire CPU (Central Processing Unit): The chip located inside the system unit of a computer that performs the processing for a computer. ALU (Arithmetic Logic Unit) FPU (Floating Point Unit) CU (Control Unit) 73

74 Hardware details 74

75 9.1 Algorithm Algorithm is a step by step method for solving a problem or doing a task. Examples: (Sum two numbers) Input: two numbers Step1: Add two numbers Step2: Return the result of step 1 End 75

76 9.2 Flowchart Flowchart is a pictorial and graphical representation of an algorithm. Example : (Sum of two numbers) 76

77 9.2 Flowchart continued Start Input A,B Sum=A+B Print Sum Stop 77

78 9.3 Pseudo code Pseudo code is an English like representation of an algorithm. Example : Begin input x input y sum = x + y print sum End 78

79 10.1 Machine Language Machine language is a binary-based language, that the computer can run directly. Instruction are in the forms of binary number such as 0 & 1. Example: The only language understood by a computer is machine language. 79

80 10.2 Assembly Language A special program called assembler that is use to translate symbolic code into machine language, known as assembly language. Example: A=00001 B=00010 C=

81 10.3 High Level Language High level languages are portable to many different computers. Example : C, C++,C#, Java. Compilation:- In High level languages, symbolic code {A,B} must be convert to machine language {0001,0010}. This process of conversion is called compilation. 81

82 Summary of Computer Languages HIGH MIDDLE High Level Language use complier for conversion of symbols to machine language. Ex:- C++,Java Assembly Language uses special program assemblers, for conversion of symbols to machine language. LOW Machine language is base on Binary Number. Computer understand only machine language. Ex:

83 11.1 What is Network Network is a collection of computers and other hardware devices that are connected together to share hardware, software, and data. Benefits of Network: 1. Share resources (Printers) 2. Access Internet 3. Exchange Data & Documents 83

84 11.2 Types of Networks LAN (Local Area Network) MAN (Metropolitan Area Network) WAN (Wide Area Network) 84

85 LAN (Local Area Network) LAN is a network that connects devices located in a small geographical area, such as a home, office building, or school. Computers are connected via cables in LAN 85

86 MAN (Metropolitan Area Network) MAN is a network designed to serve a metropolitan area such as a city or country. Computers are connected via wireless MANs 86

87 WAN (Wide Area Network) WAN is a network that connects devices located in a large geographical area such as world. Computers are connected via wireless in WAN 87

88 Types of Networks: Network Types Definition Example LAN (Local Area Network) MAN (Metropolitan Area Network) WAN (Wide Area Network) LAN is a network designed to work for small area, such as Home, School & Office, MAN is a network designed to work for medium or metropolitan cities area. WAN is a network designed to work for Large area such as world STC Modem for Home STC Internet Provider WWW: World Wide Web internet 88

89 11.3 Internet and benefits Internet:- The largest computer network, linking millions of computers all over the world. Benefits of Internet: Web Browsing Chatting and Entertainment Communication & business 89

90 12.1 Operating System Operating system is a collection of programs that manage and coordinate the activities within a computer system. Note: Operating System serves as an intermediary between the user & computer. Example of Operating system: 90

91 What are benefits/ operations of operating system? 1. Boot Process: Start up computer and load operating files into the memory. 2. User interface: Translates the user instruction to control hardware and feedback it to the user. 3. File management: Keeping track of the files stored on a PC so that they can be retrieved when needed. 4. Memory management: Optimizing (Minimize) the use of main memory (RAM). The operating system allocates RAM to programs as needed. 91

92 12.3 Types of Operating System User Interfaces. Command Line Interface GUI (Graphical User Interface) Operation System User Interface Command Line Interface Graphical User Interface Definition A user interact by command from keyboard with the computer. A user interact by graphics with the computer. Examples DOS (Disk Operating System) Linux Unix Windows XP, Vista Apple MAC 92

93 Command line Interface A user interface in which commands are typed on a keyboard. Examples: DOS (Disk Operating System) LINUX UNIX 93

94 GUI (Graphical User Interface) A graphically based interface allows a user to communicate with computer easily by graphic. Examples of GUI: 1.Microsoft Windows Windows vista Windows XP Windows 7 2.Apple macchntosk (MAC ) Has a high level of multimedia functions and connectivity IOS of Apple iphone. 94