UNIVERSITI TENAGA NASIONAL “Generates Professionals” MODULE 2 : Part 2 INTRODUCTION TO HARDWARE & SOFTWARE

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Module Objectives At the end of the module, students should be able to: –identify the two major components of operating system software –understand why a computer isn’t useful without an operating system –describe the five basic functions of an operating system –describe what happens when the computer is turn on –state three major types of user interfaces –describe the concept of software versions and systems requirements –identify the differences between types of software

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Operating System Software System software includes all of the programs needed to keep a computer and its peripheral devices running smoothly Two major components of system software are: – Operating systems (OS) – System utilities

UNIVERSITI TENAGA NASIONAL “Generates Professionals” The Operating System (OS): The Computer’s Traffic Cop The operating system is a set of programs that perform certain basic functions with a specific type of hardware Among the functions of the OS are: –Starting the computer –Managing programs –Managing memory –Handling messages from input and output devices –Enabling user interaction with the computer

UNIVERSITI TENAGA NASIONAL “Generates Professionals” OS  Starting the Computer Booting – The process of loading or reloading the operating system into the computer’s memory The booting processes are: –Cold boot – Loads the OS when the power is turned on –Warm boot – Reloads the OS when the computer is already on

UNIVERSITI TENAGA NASIONAL “Generates Professionals” The step-by-step booting process (click for each step): BIOS is loaded Power-on Self-test is completed Operating System is loaded System configuration is accomplished System Utilities are loaded Users are authenticated Starting the Computer

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Step 1: The BIOS and Setup Program BIOS (Basic Input/Output System) – The part of the system software that includes the instructions that the computer uses to accept input and output ›ROM loads BIOS into the computer’s memory Setup program – A special program containing settings that control the computer’s hardware ›The program can be accessed while the BIOS information is visible **ROM (Read Only Memory) – Permanent and unchanging memory **Load – To transfer from a storage device to memory

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Step 2: The Power-On-Self-Test (POST) POST (Power-On-Self-Test) – A series of tests conducted on the computer’s main memory (RAM), input/output devices, disk drives, and the hard disk BIOS conducts a POST to check the input/output system for operability The computer will produce a beeping sound and an error message will appear on the monitor if any problems are encountered

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Step 3: The Operating System (OS) Loads BIOS searches for the OS Settings in the CMOS (Complementary Metal- Oxide Semiconductor)  determine where to look for the OS The operating system’s kernel is loaded into the computer’s memory The OS takes control of the computer and begins loading system configuration information

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Step 4: System Configuration The system is configured from the operating system’s registry Drivers are loaded into memory **Registry – A database that stores information about peripherals and software **Peripheral – Device connected to a computer **Drivers – A utility program that makes peripheral devices function properly

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Step 5: System Utilities Loads System utilities are loaded into memory –Volume control –Antivirus software –PC card unplugging utility

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Step 6: Users Authentication Authentication or user login occurs –User name –Password The user interface starts, enabling user interaction with computer programs

UNIVERSITI TENAGA NASIONAL “Generates Professionals” OS  Managing Applications Single-tasking operating systems run one application program at a time Multitasking operating systems have the ability to run more than one application program at a time Multitasking is accomplished by: –A foreground application – The active program or program in use –One or more background applications – Inactive program(s) or program(s) not in use

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Background application Foreground application Example of Multitasking

UNIVERSITI TENAGA NASIONAL “Generates Professionals” OS  Managing Memory Computers use memory to make processing more fluid The operating system allocates memory areas for each running program; it keeps programs from interfering with each other The operating system uses virtual memory as an extension of random access memory (RAM)

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Managing Virtual Memory least recently used data or program instructions page swapped out swap file Virtual memory management hard disk page swapped in most recently transferred data or program instructions memory

UNIVERSITI TENAGA NASIONAL “Generates Professionals” OS  Handling Input and Output Input and output devices generate interrupts, or signals, that tell the operating system that something has happened The OS provides interrupt handlers or mini-programs that begin when an interrupt occurs Interrupt request (IRQ) lines handle the communications between input/output devices and the CPU An IRQ conflict causes system instability when two devices try to use the same IRQ line

UNIVERSITI TENAGA NASIONAL “Generates Professionals” OS  Providing the User Interface The user interface is that part of the operating system with which the user interacts with a computer User interface functions: –Start application programs –Manage disks and files –Shut down the computer safely

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Command-Line Interface Command-line: –The user is required to type keywords or commands in order to enter data or give instructions

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Menu-driven User Interface Menu-driven: –Text-based menus are used to show all of the options available to the user

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Graphical User Interface (GUI) Graphical user interface (GUI): –Uses graphics to create a desktop environment –Icons (small pictures) represent computer resources –Programs run within on-screen windows

UNIVERSITI TENAGA NASIONAL “Generates Professionals” System Utilities: Tools for Housekeeping System utilities are programs that help the operating system manage the computer system’s resources Types of utilities: –Backup software –Antivirus software –Disk scanning –Disk de-fragmentation –File management –File-searching software –File compression

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Application software refers to programs that enable the user to be productive when using the computer Application Software

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Personal Productivity Word Processing Spreadsheets Address Books Multimedia/Graphics Desktop Publishing Photo Editing 3D Rendering Internet Web Browsers Home/Education Personal Finance Tax Preparation Reference Games General Purpose applications are applications used by many people to accomplish frequently performed tasks General-Purpose Applications

UNIVERSITI TENAGA NASIONAL “Generates Professionals” System Requirements System requirements refers to the minimum level of equipment needed to run a program – Platform– PC or MAC – Microprocessor – Drive– 3.5 Floppy or CD-ROM – RAM – Available hard disk space Sample Minimum System Requirements Operating System with: –PC running Windows 2000 Professional version, Windows XP Professional version, or Windows Server –PC running one of the following Linux distributions: Red Hat Enterprise Version 3, SLES 8, SLES 9, Suse 8.0, Suse 8.1, Suse 8.2, and Suse 9.0 using desktops KDE or GNOME only Attached graphics display 300 MB free disk space 512 MB of memory, minimum, though 1 GB is preferred 1 Ghz CPU

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Software producers include a version number with their products Version numbers identify the release of the program being used Recent releases have numbers greater than earlier releases (Recent Ver. 6.0; Earlier Ver. 1.0) –Whole numbers are major revisions (1.0, 2.0, 3.0, etc.) –Decimal numbers refer to maintenance releases or updates and fixes (1.1, 1.2, 1.3, etc.) Software Version

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Most computer software is copyrighted Software piracy – Infringing on a program’s copyright –Copyrighted software can not be: Copied Altered Used on more than one computer Commercial Software, Shareware, Freeware and Public Domain Software

UNIVERSITI TENAGA NASIONAL “Generates Professionals” Types of copyrighted software: – Commercial – Buy before using it – Shareware – Try it before you buy it – Freeware – Free software, but it can’t be copied and/or sold Public domain software is not copyrighted. There are no restrictions on using, copying, altering, or selling the software  Open Source Commercial Software, Shareware, Freeware and Public Domain Software