1. Emad Salem

2. CHAPTER (1) COMPUTER HARDWARE

3. Computer A computer is a machine that can be programmed to process data (input) into useful information (output).computerdatainformation

4. Computer system The components of a computer system are: 1. Hardware: Physical components like Screen, Cables, Key-board, system box and printer. Note: the hardware cannot do any thing without software. 2. Software : A set of instructions that tells the computer what to do and how to do it. Such as : Word processing,Computer games and Graphics programs. 3. Users: A person who uses the software on the computer to do some tasks.

5. Computer operations 1. Receive input: (Data raw facts). 2.Process data: according to predefined instruction. 3.Produce output: (information which is meaningful data)

6. DataData & InformationInformation Data is the raw material to be processed by a computer. Data Information--data that is organized, meaningful, and useful. Information

7. Input devices accept data or commands in a form that the computer can use; they send the data or commands to the processing unit. Processor, more formally known as the central processing unit (CPU), has electronic circuitry that manipulates input data into the information people want. The central processing unit actually executes computer instructions. Output devices show people the processed data-- information--in understandable and usable form. Storage usually means secondary storage, which consists of secondary storage devices such as disk-- hard disk or diskettes or some other kind of disk--that can store data and programs outside the computer itself. These devices supplement memory or primary storage, which can hold data and programs only temporarily.

9. Input Input is data to be accepted into the computer. Input

10. Typing on a keyboard. The keys on a computer keyboard are arranged in much the same way as those on a typewriter. The computer responds to what you enter; that is, it "echoes" what you type by displaying it on the screen in front of you.keyboard

11. Input Pointing with a mouse. a mouse, which translates movements of a ball on a flat surface to actions on the screen.mouse

12. Input Scanning with a wand reader or bar-code reader. which uses laser beams to read special letters, numbers, or symbols such as bar-codes on products.wand readerbar-code reader

13. Central Processing Unit (CPU) Processes raw data into meaningful, useful information. The CPU interprets and executes program instructions and communicates with the input, output, and storage devices.

14. Output Output, which is raw data processed into usable information, is usually in the form of words, numbers, and graphics. Output

15. Screen Can vary in its form of display, producing text, numbers, symbols, art, photographs, and even video, in full color.

16. Printers Produce printed reports as instructed by a computer program. Many printers, particularly those associated with personal computers, can print in color.

17. storage primary storage Memory ROMRAM Secondary storage magnetic disks USB Flash Memory hard disk Optical disks (CD-ROMs) magnetic tape

18. Primary StoragePrimary Storage (Memory) Memory holds the input data before processing and also holds the processed data after processing, until the data is released to the output device.

19. Secondary Storage Provides additional storage separate from memory. Recall that memory holds data and programs only temporarily. The two most common secondary storage media are magnetic disks and magnetic tape.

20. Magnetic Disk 1. Diskette usually consists of a magnetic disk 3 1/2 inches. Diskette 2. Hard disks hold more data and offer faster access than diskettes do. Hard disks 3. Optical disks, such as CD-ROMs, use a laser beam to read large volumes of data. Optical disksCD-ROMs 4. Flash Memory.

21. Magnetic Tape Usually used for backup purposes. Tape drive

22. Networking Many organizations find that their needs are best served by a network, a computer system that uses communications equipment to connect computers and their resources. Resources include printers and hard disks and even software and data.

23. Types of Networks Local Area Network (LAN): Often organizations use a network of personal computers, which allows users to operate in cooperation with other computers, exchanging data and sharing resources. Local Area Network (LAN) ex.: Internal Network in companies. Wide Area Network (WAN): Users who connect their computers to other computers via the phone lines or wireless, must use a hardware device like a modem. Wide Area Network (WAN) modem ex.: The Internet.

24. The Internet Internet (International Network) The largest and most far-flung network system of them all, connecting users worldwide.

25. Classification of Computers 1- Supercomputers. 2- Mainframes. 3- Personal Computers. 4- Notebook Computers. 5- Personal Digital Assistants (PDA).

26. 1- Supercomputers The most powerful. The most expensive. the fastest: They can process trillions of instructions per second. supercomputer customers: agencies of the government.

27. 2- Mainframes Large computers used by businesses such as banks, airlines, and manufacturers. process very large amounts of data quickly.

28. 3- Personal Computers personal computers are called (PCs), Desktop computers, microcomputers or home computers. personal computers (PCs)microcomputershome computers Now, for a few hundred dollars, anyone can own a personal computer. At the low end, a cheap PC has less of everything: a slower and less powerful microprocessor, less memory, a smaller and less crisp screen, less hard drive space, and fewer software choices. Nevertheless, cheap PCs perform primary functions. Customers who want a computer mainly for basic applications such as word processing, personal finance, record-keeping, games, and access to the Internet. Ex.: IBM, Apple Macintosh.

29. 4- Notebook Computers Notebook computers are wonderfully portable and functional, and they are popular with travelers who need a computer that can go with them. Somewhat larger, heavier versions of these computers are known as laptop computers. The memory and storage capacity of notebook computers today can compete with those of desktop computers. Notebooks have a hard disk drive and most accept diskettes, so it is easy to move data from one computer to another. Many offer a CD- ROM drive. Furthermore, notebooks can run most software available.

30. 5- Personal Digital Assistants (PDA) Also called pen-based computers.pen-based computers Handheld computers that accept handwritten input directly on a screen