Copyright © 2003 Prentice Hall, IncSlides created by Bob Koziel

2 Copyright © 2003 Prentice Hall, Inc DILARANG KERAS AWAS…..  I NEXT SLIDE

3 Copyright © 2003 Prentice Hall, Inc Understanding the Computer A computer is a machine that, under a program’s direction, performs four basic operations: input, processing, output, and storage. A program is a list of instructions that tells a computer how perform the four operations. NEXT SLIDE

4 Copyright © 2003 Prentice Hall, Inc Input The first operation. The computer performs arithmetic or comparison operations on data. Electrical impulses representing words, numbers, images, or sounds. NEXT SLIDE

5 Copyright © 2003 Prentice Hall, Inc Processing The second operation. The computer performs arithmetic or comparison (logical) operations on the data. Performed at a very high speed. Arithmetic 4+16=20 Logic 728>546 NEXT SLIDE

6 Copyright © 2003 Prentice Hall, Inc Output The third operation. The computer shows the results of the processing operation in a way people can understand. Data is processed into information. NEXT SLIDE

7 Copyright © 2003 Prentice Hall, Inc Storage The fourth operation. The computer saves the data or output so that it can be used again later. NEXT SLIDE

8 Copyright © 2003 Prentice Hall, Inc How Computers “Think” Computers use algorithms to solve a problem. Algorithms are step-by-step procedures. NEXT SLIDE

9 Copyright © 2003 Prentice Hall, Inc The Information Processing Cycle The computer performs the four basic operations (input, processing, output, and storage). Two types of processing cycles:  Batch processing– A lockstep sequence used by older computers.  Interactive processing– Initiating several information processing cycles in a single session; used by modern computers. Input Processing Output Storage NEXT SLIDE

10 Copyright © 2003 Prentice Hall, Inc Computer System A collection of related computer components that are designed to work together. A system includes hardware and software. NEXT SLIDE Hardware Software

11 Copyright © 2003 Prentice Hall, Inc Hardware Hardware is the computer’s physical components. The components include:  Input devices– Enable users to enter data into the computer for processing.  Processing circuitry– Components located in the system’s case that transform data into information.  Output devices– Peripherals that show the results of processing.  Storage devices– Used to store all the programs and data that the computer uses.  Communication Devices– Used to move data between computers. NEXT SLIDE

12 Copyright © 2003 Prentice Hall, Inc Input: Transforming Data into Information Key Terms Command– A type of input that tells the program what to do. Confirmation– A message that indicates if the command was or was not carried out. Keyboard– Enables the user to input characters. Pointing device– Enables the user to move an on– screen pointer. Speech-recognition– A program that enables the computer to transcribe spoken words into text. NEXT SLIDE

13 Copyright © 2003 Prentice Hall, Inc KeyboardMouse– pointing device Microphone– speech - recognition Digital Cameras NEXT SLIDE Input Devices

14 Copyright © 2003 Prentice Hall, Inc Processing: Transforming Data into Information Key Terms Central processing unit (CPU)– The computer’s processing circuitry. It is also called a microprocessor. Chip– A wafer of silicon that contains a complex electronic circuit. Motherboard– The computer’s main circuit board. Memory– Chips that store program instructions. Random access memory (RAM) is the most important type. Expansion slots– A receptacle designed to accept a plug-in expansion card. Expansion card– Used to connect peripherals (input/output devices) to the motherboard. NEXT SLIDE

15 Copyright © 2003 Prentice Hall, Inc I NEXT SLIDE Components of the CPU Control unit– Coordinates and controls all parts of the computer system. Arithmetic-Logic unit– Performs arithmetic or logical operations. Registers– Store the most frequently used instructions and data.

16 Copyright © 2003 Prentice Hall, Inc CPUs at Work I NEXT SLIDE Control Unit– Manages four basic operations (fetch, decode, execute, and write-back).  The machine cycle or processing cycle: Instruction Cycle  Fetch- Gets next program instruction from the computer’s memory.  Decode- Figures out what the program is telling the computer to do. Execution Cycle  Execute- Performs the requested action.  Write-back (Store)- Writes (stores) the results to a register or to memory. Arithmetic-Logic Unit (ALU)– Performs basic arithmetic or logic operations.  Adds, subtracts, multiplies, and divides  Compares data to determine which one is larger or smaller.

17 Copyright © 2003 Prentice Hall, Inc Control unit ALU Memory Click to animate. Click one time only NEXT SLIDE The Processing Cycle

18 Copyright © 2003 Prentice Hall, Inc Microprocessor Printer Port Video Port PCI Slots Memory Slots AGP Slot Chipset Click on terms to view larger images and information Keyboard / Mouse Ports The Motherboard