Information Technology INT1001 Lecture 6 Computer Software 1

Computers Are Your Future Tenth Edition Chapter 4: System Software Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall2

Software Software can be grouped as system software or application software System software includes the programs that assist with the proper functioning of the computer. Application software includes the programs used to perform tasks. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall3

System Software Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall4

The Operating System System software consists of all the programs that enable the computer and its peripheral devices to function smoothly. System software is divided into two main categories: The operating system (OS) System utility programs 5Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall

The Operating System Management of the resources of a computer are performed by the computer’s operating system (OS). The coordination of the functions of a computer’s hardware is the prime responsibility of the operating system. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall6

The Operating System The five basic functions carried out by the operating system are: Starting the computer Managing applications Managing memory Handling input and output device messages Providing a user interface for communication Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall7

The Operating System The first function of the operating system, starting the computer, involves six steps. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall8

The Operating System The operating system’s second function is managing applications. Single-task operating systems from the past were only able to run one application at a time. Today’s multitasking operating systems permit more than one application to be used at a time. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall9

The Operating System The operating system’s third function is managing memory. The operating system attempts to allocate memory, RAM, to each program being run without interference. Through the use of virtual memory, where a portion of the hard disk is used as an extension of RAM, additional memory is available. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall10

The Operating System The operating system’s fourth function is managing input and output. The operating system uses drivers, programs containing information regarding specific computer input and output devices, to communicate with those devices. Interrupts, signals created by input and output devices, notify the operating system when an action has been taken. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall11

The Operating System The operating system’s fifth function is providing a user interface. The user interface allows the user to: Start application programs Manage storage devices Safely shut down the computer properly Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall12

The Operating System There are three types of user interfaces: Graphical user interface (GUI) Menu-driven user interface Command-line user interface Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall13

The Operating System The graphical user interface uses graphics called icons, small images that represent various computer resources, to initiate actions. These icons appear on the desktop, the work area that is created once the operating system has been loaded into memory. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall14

The Operating System The menu-driven user interface provides text-based menus, which display appropriate user options that are available. The command-line user interface forces the user to type commands line by line to instruct the operating system about the desired action(s) to be taken. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall15

Exploring Popular Operating Systems Operating systems are usually already installed on a computer when you purchase it. The most commonly supplied operating system is Microsoft Windows. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall16

Exploring Popular Operating Systems Microsoft Windows Vista, the replacement for Windows XP, is intended for both home and professional use. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall17

Exploring Popular Operating Systems Microsoft Windows Mobile provides a user interface in a simplified Windows format for handheld devices such as smartphones and PDAs. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall18

Exploring Popular Operating Systems The Mac OS used on Macintosh personal computers is favored by its users for the operating system’s security, stability, and simplicity. UNIX was developed to work in a secure computer network, but unfortunately, its many versions are not compatible and can be hard to use. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall19

Exploring Popular Operating Systems Linux is a powerful open source operating system that is freely available to any user. MS-DOS (DOS), a disk operating system, is a command-line user interface operating system that is not user friendly. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall20

System Utilities: Housekeeping Tools System utilities (utility programs) are system software programs that are essential to effective management of the computer system. System utilities include software that performs such tasks as backing up files, providing antivirus protection, and compressing files. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall21

System Utilities: Housekeeping Tools Backup software duplicates data found on the hard disk to a backup device. Full backups include all files and data. Incremental backups include only those files changed or added since the previous backup. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall22

System Utilities: Housekeeping Tools Antivirus software provides protection from computer viruses. The two most popular antivirus programs are: Norton AntiVirus McAfee VirusScan Plus Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall23

System Utilities: Housekeeping Tools The utility software used to organize and manage data on your disk is called the file manager. The file manager enables you to: Copy files Determine how and where files are stored Delete files Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall24

System Utilities: Housekeeping Tools Disk scanning programs find and resolve problems that result from disk file storage. Disk cleanup utilities remove unnecessary files, which results in saving space. Disk defragmentation programs reorganize stored data in a more efficient manner. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall25

System Utilities: Housekeeping Tools File compression utilities: Decrease the size of files, resulting in faster downloads. Create archives by storing files in a special format. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall26

System Utilities: Housekeeping Tools Windows Update, an operating system update service provided by Microsoft, enables users to keep their operating system current with external modifications. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall27

Application Software: Tools for Productivity Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall28

General-Purpose Applications Application software is any program that gives the user the ability to complete work on the computer. General-purpose applications are the programs that enable users to complete common tasks. 29Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall

General-Purpose Applications General-purpose applications include: Personal productivity programs Multimedia and graphics software Internet programs Home and education programs Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall30

General-Purpose Applications Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall31

Tailor-Made Applications Software designed for specific businesses or users is known as a tailor-made application. Tailor-made applications normally cost more than general-purpose applications because of their development costs. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall32

Tailor-Made Applications When an application is not available, custom software, software developed for a user’s specific needs, may be necessary. Packaged software is developed for the mass market. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall33

Standalone Programs, Integrated Programs, & Software Suites A fully self-contained program is called a standalone program. Advantages: Users can purchase and install standalone programs separately. Standalone programs function by themselves. Disadvantages: Standalones take up a lot of storage space. Standalones do not share resources. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall34

Standalone Programs, Integrated Programs, & Software Suites Integrated programs provide all the leading productivity programs in one package. Advantages: Integrated programs are easy to learn. Integrated programs share the same interface. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall35

Standalone Programs, Integrated Programs, & Software Suites Disadvantages: The individual modules of integrated programs usually have fewer features than are found in standalone programs or software suites. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall36

Standalone Programs, Integrated Programs, & Software Suites A software suite is an interconnected bundle of programs. Advantages: The programs within a suite share resources. The programs within a suite are designed to work together. These applications share common program code, interfaces, and drivers. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall37

Standalone Programs, Integrated Programs, & Software Suites Software suites, also called office suites, usually include: Word processing programs Spreadsheet programs Presentation graphics programs Database programs Personal information managers (PIMs) Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall38

Standalone Programs, Integrated Programs & Software Suites Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall39

Standalone Programs, Integrated Programs, & Software Suites Web-hosted technology is a new variety of office suite that enables users to upload files online for viewing, editing, and collaboration purposes. Advantages: Web-hosted technology is usually free. It makes sharing files and collaboration easier. Web-hosted technology helps avoid file-sharing problems. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall40

System Requirements & Software Versions System requirements outline the minimal level of resources that a program requires. Releases of programs are cited by a year or version number. In a version number, a decimal number indicates a maintenance release. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall41

System Requirements & Software Versions Time-limited trial versions are occasionally offered for commercial programs by software companies. Beta versions of software are sometimes available to users. Software is in the final testing stages and may contain bugs. Access is free. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall42

System Requirements & Software Versions Software is kept current through software upgrading. Small fixes to software are called patches. Large or major fixes to software are called service packs or service releases. Software can be distributed through the Internet, not just purchased in stores. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall43

System Requirements & Software Versions Documentation can be in print or downloaded from the Internet. Brief tutorials Read Me files Help files Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall44

Software Licenses & Registration The contract included with purchased software, which permits the user to install the program on one computer, is known as a software license. The contract that gives organizations the right to install copies of programs on a precise number of computers is known as a site license. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall45

Software Licenses & Registration Commercial Software Users must purchase before using Examples: Microsoft Office Adobe Acrobat Apple iLife Shareware You may try software before purchasing If you like it, pay for it and continue use Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall46

Software Licenses & Registration Freeware Free to users as long as users do not sell it to others Public domain software Copyright-free software Can modify or sell Copy-protected software Internal process prohibits making unauthorized copies Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall47

What You’ve Learned System software is made up of two main parts: the operating system and system utilities. Computers need software to work. The operating system coordinates the functions of hardware and supports the application software. 48Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall

What You’ve Learned The operating system has five functions: starting the computer, managing applications, managing memory, handling messages from input and output devices, and providing an interface for communication. 49Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall

What You’ve Learned A six-step process occurs each time you start or restart a computer. There are three types of user interfaces: graphical user interfaces (GUIs), menu-driven user interfaces, and command-line user interfaces. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall50

What You’ve Learned For personal computers, Microsoft Windows and Mac OS X are the two major operating systems. System utilities include such programs as backup software, file managers, and file compression utilities. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall51

What You’ve Learned Backup procedures should include a full backup, followed by periodic incremental backups. Troubleshooting skills are required when you use a computer. Do only what you feel comfortable doing, then enlist the help of a professional. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall52

What You Will Learn Understand how system software supports application software. List the most popular types of general- purpose applications. Discuss the advantages and disadvantages of standalone programs, integrated programs, and software suites. 53Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall

What You Will Learn Discuss the advantages of Web-hosted technology and file compatibility. Explain the concept of software versions and software upgrades. Understand how commercial software, shareware, freeware, and public domain software differ. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall54

What You Will Learn Describe the essential concepts of application software and the skills needed to use it. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall55

What You’ve Learned System software supports application software, the programs that give the user the ability to complete work on the computer. General-purpose software includes personal productivity programs, multimedia and graphics software, Internet programs, and home and education software. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall56

What You’ve Learned Types of programs available to users include standalone programs, integrated programs, and suites of personal productivity software. Office suites, which incorporate Web- hosted technology, are gaining popularity with today’s users. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall57

What You’ve Learned New or updated versions of software are usually cited with a version number. Small changes to software are defined as patches, and larger changes or fixes are known as service packs or service releases. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall58

What You’ve Learned Software can be categorized as commercial, shareware, freeware, and public domain software. Users should learn to install applications, start applications, select options, and exit the applications to use their computers effectively. Copyright © 2009 Pearson Education, Inc. Publishing as Prentice Hall59