Chapter 1 WHAT IS A COMPUTER Faculty of ICT & Business Management Tel : BCOMP0101 Introduction to Information Technology

BCOMP0101Introduction to Information Technology2 What is a computer? A computer is an electronic device, operation under the control of instructions stored in its own memory that can accept data, manipulate the data according to specified rules, produce result and store the results for future use. Tablet PC

BCOMP0101Introduction to Information Technology3 What does a computer do? Whether small or large, computers can perform four general operations. The four general operations are: Input Process Output Storage

BCOMP0101Introduction to Information Technology4 Information processing cycle Data is a collection of unprocessed items (raw facts), which include text, numbers, images, audio and video. Information is data that is organized, meaningful and useful to one or more people. Instructions are the steps that tell the computer how to perform a particular task.

BCOMP0101Introduction to Information Technology5 Information Processing Cycle The flow of the raw data  information COMPUTER (instructions) DataINFORMATION Storage devices End user / monitor

BCOMP0101Introduction to Information Technology6 The Components of a computer INPUT DEVICES Mobile device Web cam PDA Microphone -Allows data or instructions entered into the computer

BCOMP0101Introduction to Information Technology7 Con. OUTPUT DEVICES Monitors Output devices – Conveys information to one or more people LCD monitor CRT monitor

BCOMP0101Introduction to Information Technology8 System Unit System Unit - Box-like case containing electronic components of the computer that are used to process data. Motherboard is a circuit board that has many circuitry lines and components. 2 main components on motherboard: processor and memory. MotherboardProcessorMemory

BCOMP0101Introduction to Information Technology9 Storage Devices Holds data, instructions and information for future use permanently. Storage Devices ZIP DISK

BCOMP0101Introduction to Information Technology10 Communications Devices A hardware component that enables a computer to send (transmit) and receive data, instructions and information to and from one or more computers. Modem

BCOMP0101Introduction to Information Technology11 Why is Computer so Powerful? Speed – computes billions of operations in 1 second Reliability and consistency – low failure rate. Higher reliability of components enables the computer to produce consistent results Accuracy – error free results. Garbage in, garbage out Storage – can transfer data quickly from storage to memory, process it, and store it again for future use. Available almost any time. Communications – can communicate with other computers and devices. Can share any 4 information processing cycle – input, process, output and storage.

BCOMP0101Introduction to Information Technology12 The Internet The Internet is a worldwide collection of networks that connects millions of businesses, government agencies, educational institutions and individuals. Reasons to use the Internet: –Communicate with and meet other people around the world. –Access to a wealth of information, news and research findings –Shop for goods and services –Bank and invest - Take a class –Access sources of entertainment and leisure, such as online games, music, videos, books and magazines.

BCOMP0101Introduction to Information Technology13 Computer Software Software or program is a series of instructions that tells the computer to do and how to do it. Installing is the process of setting up the software to work with the computer and other hardware components. Run the program means to use it. Load the program means to call the program from storage media and place into memory. Execute the program means to carry out instructions. Graphical user interface (GUI, gooey) is the “space” where we interact with the software using text, graphics, and visual images such as icons.

BCOMP0101Introduction to Information Technology14 System Software System software consists of the programs that control or maintain the operations of the computer and its devices. Serves as the interface between the user, the application software and computer’s hardware. 2 types: operating system and utility program

BCOMP0101Introduction to Information Technology15 Operating System OS is a set of programs that coordinates all the activities among computer hardware devices. Contains instructions that allow users to run application software. A portion is loaded into the memory from hard disk. Used by users to communicate with the computer and other software. E.g. Windows, MAC OS, LINUX, etc.

BCOMP0101Introduction to Information Technology16 Utility Program Allows user to perform maintenance-type tasks usually related to managing a computer, its devices or its programs. Usually OS provides common and important utility programs such as managing disk drives, printers, and other devices. Can be purchase off shelves or online to perform additional computer management functions. E.g. Norton Ghost, Norton Utilities, etc.

BCOMP0101Introduction to Information Technology17 Application Software Consists of programs that perform specific tasks for users. E.g. Web browser, word processing software, spreadsheet software, database software, presentation software, photo-editing software, etc. Bundle software consists of several related application software come in a single packaging box. E.g. Microsoft Office Can be purchase off shelves or online.

BCOMP0101Introduction to Information Technology18 Software Development A programmer is a person who develops application or system software. Programmers develop programs or write the instructions that direct the computer to process data into information. Programmers must be sure the program works properly so that the computer generates the desired results. Complex programs can require thousands to millions of instructions. Programming language or program development tool is used to create computer programs. E.g. C, C++, C#, Visual Basic.NET 2003, Java, etc

BCOMP0101Introduction to Information Technology19 Categories of Computer CategoryPhysical SizeNo. Of Simultaneous Connected Users General Prize Range Personal computer (desktop) Fits on a deskUsually one (can be more if networked) Several hundred to several thousand dollars Mobile computers and mobile devices Fits on your lap or in your hand Usually oneSeveral thousand dollars or less Midrange serversSmall cabinetTwo to thousands%5,000 to $850,000 Mainframe computers Partial room to a full room of equipment Hundreds to thousands$300,000 to several million dollars SupercomputersFull room of equipmentHundreds to thousands$500,000 to more than $85 million dollars

BCOMP0101Introduction to Information Technology20 Types of computer Midrange computer Mainframe computerSupercomputers

BCOMP0101Introduction to Information Technology21 Elements of Information System Information system consists of hardware, software, data, people and procedures. Hardware must be reliable and capable of handling expected workload Software must be developed carefully and tested thoroughly Data input into the computer must be accurate Incorrect data generates incorrect information (Garbage in, garbage out)

Cont.. IT staff from IT department of a company should be highly skilled and up-to-date on the latest technology IT staff also should train users so they understand how to use the computer properly IT applications should have readily available documented procedures. These procedures should address starting, operating and using the computer. BCOMP0101Introduction to Information Technology22

BCOMP0101Introduction to Information Technology23 THE END!