Introduction to Computer Applications Lecture 1

2 What is a Computer? A computer is an electronic device, which executes software programs. It consists of two parts: hardware and software.

Computer Systems A computer program is… –A set of instructions for a computer to follow. Computer software is … –The collection of programs used by a computer Computer hardware is … –The actual physical machines that make up a computer installation. 1-3 SoftwareHardware The parts that can’t be touched are called “Software”. Characteristics: It has no physical existence. They can be realized through mind and feeling only. E.g. translators, editors, programs. Things that can be touched are called “Hardware”. Characteristics: They have physical existence, weight, color & they can be damaged or broken. E.g. monitor, mouse, printer.

1-4 Types of Computers Supercomputers Mainframe computers Minicomputers Microcomputers Page 10

1-5 Four Types of Microcomputers Desktop Notebook or laptop Tablet PC Handheld Page 11

1-6 Microcomputer Hardware Four basic categories of equipment: –System UnitSystem Unit –Input/outputInput/output –Secondary StorageSecondary Storage –CommunicationCommunication Page 11

Main Components of a Computer 1-7 System Unit

1-8 System Unit Two important components- –Processor –Memory (RAM) Page 12 Return

Slide 1- 9 Processor (CPU) The CPU (Central Processing Unit) is the brain of the computer. The CPU follows the instructions in a program and performs the calculations specified by the program. CPU has two important units –ALU ( Arithmetic logic unit does arithmetic & logical operations for computer) –Control unit ( controls the flow of information in computer)

10 Hardware Memory –Internal memory / Main memory Random Access Memory (RAM) –Main feature 1: volatile  requires continuous supply of electrical power to retain information –Functions:  Receive commands / data from keyboard  Store information ready to be sent to output  Store currently running programs/their data  Store immediate data generated by the currently running programs

1-11 Input/Output Common input devices are the keyboard and the mouse Common output devices are printers and monitors Page 13 Return

1-12 Secondary Storage Page 13 Unlike memory, secondary storage holds data and programs even if electrical power is not available The most important types of secondary media are floppy, hard, and optical disks e.g, CDROMs MemoryStorage Devices Less capacityLarger capacity Volatile -> Data is lost when power is offNon-volatile-> Data is retained even if power is off More expensiveLess expensive

1-13 Communications Page 14 Communication devices enable microcomputers to communicate with other computer systems across the globe. The modem is the most widely used communication device.

1-14 Software Two major kinds of software –System SoftwareSystem Software –Application SoftwareApplication Software Page 7

5-15 System Software Handles technical details Works with end users, application software, and computer hardware Four types of programs –Operating system –Utilities –Device drivers –Language translators Page 134

5-16 Operating System Coordinates computer resources Provide an interface between the users and computer Runs applications A collection of programs that handle technical tasks Every computer has an operating system Page 135

1-17 “End-user” software Two major categories –Basic Application or General purpose –Specialized applications Application Software Page 9

3-18 Common Features Graphical User Interface (GUI) Icons Windows Menus Help Toolbars Page 64

3-19 Computer Applications: Word Processors Used to create text-based documents –Memos, letters, and faxes –Newsletters, manuals, and brochures Word processing programs –Microsoft Word –Corel WordPerfect –Lotus Word Pro Page 68

3-20 Word Processor Features Word Wrap Editing –Thesaurus –Find and Replace –Spelling and grammar checkers –Copy and paste features –Add images to your document Formatting –Font and font sizing –Character effects –Bulleted and numbered lists Page 68

3-21 Computer Applications: Spreadsheets Programs that manipulate numeric data Spreadsheet programs –Microsoft Excel –Corel Quattro Pro –Lotus Page 71

3-22 Spreadsheet Features Workbook files Worksheet or spreadsheet or sheet Formulas Functions Analytical graphs or charts What-if Analysis Page 71

3-23 Computer Applications: Presentation Graphics Programs that create visually interesting presentations Presentation programs –Microsoft PowerPoint –Corel Presentations –Lotus Freelance Graphics Page 79

3-24 Presentation Graphics Features Slides AutoContent wizard Design templates Master slide Page 79

3-25 Computer Applications: Database Management Systems DBMS A collection of related data Sets up a structure for data storage Database programs –Microsoft Access –Corel Paradox –Lotus Approach Page 76

3-26 Database Features… study in detail later Relational Tables –Records –Fields Record sorting Queries Forms Reports Page 76

1-27 Page 14 Internet - It is a network of almost all the computers in the world. You can browse through much more information than you could do in a library. That is because computers can store enormous amounts of information. You also have very fast and convenient access to information. Computer Applications

2-28 Common Internet Uses Communicating –Exchange –Discussion Groups –Video conferencing Online shopping or e-retailing or e-tailing –Cybermall –E-bay Searching –Virtual Libraries Page 30

2-29 Common Internet Uses Entertainment: Music, Games, Movies Education or e-learning : Instead of a book it is easier to learn from an E-learning software. Page 30

1-30 Page 14 Computers in Medicine - –You can diagnose diseases. You can learn the cures. –Software is used in magnetic resonance imaging to examine the internal organs of the human body. –Software is used for performing surgery. –Computers are used to store patient data. Computer Applications

1-31 Page 14 Computers in Business –Shops and supermarkets use software, which calculate the bills. –Taxes can be calculated and paid online. –Accounting is done using computers. –One can predict future trends of business using artificial intelligence software. –Software is used in major stock markets. –One can do trading online. –There are fully automated factories running on software. Computer Applications

1-32 Page 14 Banks - All financial transactions are done by computer software. They provide security, speed and convenience. Travel - One can book air tickets or railway tickets and make hotel reservations online. Telecommunications - Software is widely used here. Also all mobile phones have software embedded in them. Airplanes – Pilots train on software, which simulates flying. Weather analysis – Supercomputers are used to analyze and predict weather. Computer Applications…few others