Computer Skills1 by Maram Bani Younes This course consist of three main topics: Computer System 1.Hardware 2.Software A.System Software (Ms-DOS, MS-Windows). B.Application software (games, office). 3.user Offices Word Excel Power Point Access Outlock..etc. Internet
Computer Skills1 by Maram Bani Younes The Computer Computer : is an information processing machine used in different departments and organizations. It performs three main operations: Receive input (data: raw facts). Process it according to predefined instructions. Produce output (information: meaningful data).
Computer Skills1 by Maram Bani Younes Computer Operations Computer Receive Produce Data: raw facts. Information: meaningful data. Data Information Process
Computer Skills1 by Maram Bani Younes Computer Components The major components of any computer are: Input Devices: this group consists of devices that enable the computer to receive (insert) data. System unit (CPU unit): This unit contains many components used to process data (CPU, Memory). Output Devices: this group consists of devices that translate the information processed by the computer into a form that humans can understand (display information).
Computer Skills1 by Maram Bani Younes Hardware Hardware: physical components in the computer system like Screen, Cables, Keyboard and printer. Cannot do anything without software. Three main group will be studied in details: Central Processing Unit (CPU). Memory (primary && secondary). I/O devices.
Computer Skills1 by Maram Bani Younes Central Processing Unit (CPU) The CPU is the central electronic chip that determines the processing power of the computer. it is the brain of computer. It interprets and executes the instruction contained in software program (process data inside computer). It determines how fast your computer will run. It is measured by MHz (Mega Hertz).
Computer Skills1 by Maram Bani Younes CPU Parts CPUs have three basic parts: 1.Arithmetic and Logic Unit (ALU). Performs arithmetic operations and logical operations and control the speed of those operations. Arithmetic operations: +, -,*, /. Logical operations: >, =,. 2.Control Unit (CU). 1.Tells the rest of computer system how to carry out a programs instructions. 2.It directs the movement of electronic signals between main memory and the arithmetic unit. 3.It directs the electronic signals between main memory and the input and output devices.
Computer Skills1 by Maram Bani Younes CPU Parts 3. Registers or Immediate Access Memory. This is a high access memory used to immediately store: A.Data that is used by the ALU. B.Program instructions which are used by the Control Unit.
Computer Skills1 by Maram Bani Younes Memory The computer stores data and information into special places called memory, this memory enables the user to get his data whenever he want. There are two main types of memory: Primary memory. Secondary memory.
Computer Skills1 by Maram Bani Younes Primary Memory Forms of Primary Memory (Primary Storage) are: RAM. Random Access Memory The location where data and programs are stored. Volatile : the data is only there while the power to the computer is turned on. It is comprised of chips attached to the motherboard. Its speed measured in Megahertz (MHs). Its size 16, 32,64 or 128 Megabyte. ROM. Read Only Memory This a very small capacity main memory. It keeps instructions which make the computer work when turning it on. Its not volatile. The computer cannot write on it.
Computer Skills1 by Maram Bani Younes Cache Memory. It is linked to the CPU. It has very fast chips. Keep frequently used programs and data. It helps to increase the speed of the computer. It reduces the gap speed between the RAM and the CPU. Flash Memory. Memory that is divided into blocks, so it saves and erased data in faster way. It is a non volatile memory. Can be used to: To save BIOS in computers. In mobiles. In portables. In digital camera. Printers.
Computer Skills1 by Maram Bani Younes Secondary Memory Also called: Storage Devices. Secondary Storage System. External Storage. This memory is used to keep software, programs and data permanently.
Computer Skills1 by Maram Bani Younes Secondary Memory Types Hard Disk Located within the CPU. (high speed & non portable). Capacity 20 GB or more. (high capacity). Floppy Disk Small disk with low speed and portable. Capacity 1.4 MB. CD-ROM (Compact Disk Read Only Memory) It is an optical disk (uses laser to read the information). High speed memory (less than Hard Disk). Capacity 700 MB. DVD (Digital Versatile Disk). High capacity development of CD-ROM. Capacity (4.7-17) GB.
Computer Skills1 by Maram Bani Younes Secondary Memory Types Zip Disc It is similar to floppy disks shape. (just heavier). Its capacity (100-750)MB. Magnetic Tape It is made of flexible plastic coated on one side with a magnetic material. It is used to store backup data. Smart Card It look like credit card but contains a microprocessor and memory. USB Flash Drives Easy to use. Complete freedom and mobility.
Computer Skills1 by Maram Bani Younes Data Representation in the Memory Bit : 1 or 0 (binary form). Nibble: 4 bits (a half of byte). Byte: A group of 8 Bits. Memory unit represent 1 character. it is used to measure the memory capacity. Kilobytes(KB):about 1000 byte exactly it is1024 Bytes. Megabyte(MB):about 1 million byte exactly it is1024x1024 Bytes. Gigabyte(GB): about 1 billion byte exactly it is1024x1024x1024 Bytes. Terabyte(TB): about 1 trillion byte exactly it is 1024x1024x1024x1024 Bytes.
Computer Skills1 by Maram Bani Younes Input /Output Devices Input Devices: allow you to input (insert) information to the computer. Output Devices: allow you to output (display or print) information from the computer.
Computer Skills1 by Maram Bani Younes Input Devices Keyboard Mouse Trackball Touch Pad Light Pen Scanners Bar Codes Optical Marker Reader (OMR) Magnetic Strip Joystick Microphone Digital Camera Video Camera
Computer Skills1 by Maram Bani Younes Output Devices Monitors: Video Display Units (VDU). Plotters Speakers Speech Synthesizers Projectors Printers Data Show
Computer Skills1 by Maram Bani Younes Types of Monitors Cathode Ray Tube (CRT): (Traditional screen): It is like Television screen but more clear. It is less cost and less safety than Flat one. Flat-Panel Display It is Flat screen like Liquid Crystal Display (LCD). It is more expensive and more safety than CRT.
Computer Skills1 by Maram Bani Younes Characteristics of monitors: 1. Color: depends on the construction of the monitor and the graphic adapter. 2. Size: (diagonally) 15- 17inch,19- 21. 3. Resolution: the number of displayed pixels on the screen. High resolution means clearer display. VGA :640 x 480 SVGA:800 x 600 XVGA:1024 x 768
Computer Skills1 by Maram Bani Younes Printers Printers: are devices that converts computer output into printed papers. Hard copy: refers to printed output. Software copy: refers to output that is in the form of sound or displayed on a computer screen.
Computer Skills1 by Maram Bani Younes Kinds of Printers: Laser: use Laser beam source to print documents. It is high quality, robust printer, high speed and high expensive especially the colored one. Inkjet: spray one or more colors of small droplets of ink at high speed onto paper. It is less quality, robust, speed and expensive than Laser one. Dot Matrix: use pins to strike on an inked ribbon against paper. It is less quality, robust, speed and expensive than Inkjet. Daisy Wheel: characters are raised on a wheel, which strikes the ribbon placed between them, and the paper. It is an impact, which is both slow and noisy. it produces carbon copies.
Computer Skills1 by Maram Bani Younes Input/Output Device TouchScreen: this device is both input/output; this device is a video display screen that has been sensitized to receive input from touch of a finger. Storage Devices :can be input Devices or output Devices depending on the way they are used.
Computer Skills1 by Maram Bani Younes Types of Computers According to their capacity and performance, computers are classified into seven categories:
Computer Skills1 by Maram Bani Younes Types of Computers 1.Super Computers. High capacity, very expensive. Usually used for research. 2.Mainframes. Room-sized, expensive, high speed, very powerful, large storage capacities. It is used in large organizations like Banks and government departments. It is connected to a set of terminals that could be dumb-terminals or intelligent- terminals. 3.Mini Computers. Do the same jobs as a mainframe, but on a smaller scale. 4.Personal Computers (PCs) It is small computer which has its own system (CPU, Memory, Harddisk etc.). It is not expensive and very popular. It can be set on a disk.