When selecting an operating system, you must consider the current and future requirements for application software to meet the needs of the organization. In addition, your choice of a particular operating system must be consistent with your choice of hardware. Identify and briefly describe the functions of the two basic kinds of software Outline the role of the operating system and identify the features of several popular operating systems Principles of Information Systems, Seventh Edition

Do not develop proprietary application software unless doing so will meet a compelling business need that can provide a competitive advantage Discuss how application software can support personal, workgroup, and enterprise business objectives Identify three basic approaches to developing application software and discuss the pros and cons of each Principles of Information Systems, Seventh Edition

Choose a programming language whose functional characteristics are appropriate for the task at hand, taking into consideration the skills and experience of the programming staff Outline the overall evolution of programming languages and clearly differentiate among the five generations of programming languages Principles of Information Systems, Seventh Edition

The software industry continues to undergo constant change; users need to be aware of recent trends and issues to be effective in their business and personal life Identify several key issues and trends that have an impact on organizations and individuals Principles of Information Systems, Seventh Edition

An Overview of Software Computer programs: sequences of instructions for the computer Documentation: describes program functions to help user operate computer system Systems software: set of programs that coordinates the activities of hardware and programs Application software: programs that help users solve particular problems Principles of Information Systems, Seventh Edition

Table 4.1: Classifying Software by Type and Sphere of Influence Principles of Information Systems, Seventh Edition

Systems Software: Operating Systems Operating system (OS): a set of computer programs that controls the computer hardware and acts as an interface with application programs Kernel: ties all of the components of the OS together and regulates other programs; controls the most critical processes Principles of Information Systems, Seventh Edition

Operating Systems (continued) Activities performed by the operating system: Perform common computer hardware functions Provide a user interface and input/output management Provide a degree of hardware independence Manage system memory Principles of Information Systems, Seventh Edition

Operating Systems (continued) Activities performed by the operating system: Manage processing tasks Provide networking capability Control access to system resources Manage files Principles of Information Systems, Seventh Edition

Figure 4.2: Operating system as interface between application software and hardware Principles of Information Systems, Seventh Edition

Operating Systems (continued) Common hardware functions Get input from the keyboard or some other input device Retrieve data from disks Store data on disks Display information on a monitor or printer Principles of Information Systems, Seventh Edition

Operating Systems (continued) User interface and input/output management User interface: allows individuals to access and command the computer system Command-based user interface: requires that text commands be given to the computer to perform basic activities Graphical user interface (GUI): uses icons and menus displayed on screen to send commands to computer system Principles of Information Systems, Seventh Edition

Operating Systems (continued) Application program interface (API): allows applications to make use of the operating system Memory management: control how memory is accessed and maximize available memory and storage Principles of Information Systems, Seventh Edition

Figure 4.3: Application Program Interface Links Application Software to the Operating System Principles of Information Systems, Seventh Edition

Operating Systems (continued) Processing tasks Multitasking: capability allowing more than one program to run at the same time Time-sharing: allows more than one person to use a computer system at the same time Scalability: ability of the computer to handle an increasing number of concurrent users smoothly Networking capability: features and capabilities of the OS that aid users in connecting to a computer network Principles of Information Systems, Seventh Edition

Operating Systems (continued) Access to system resources Protection against unauthorized access Logins and passwords File management: ensures that files in secondary storage are available when needed and that they are protected from access by unauthorized users Principles of Information Systems, Seventh Edition

Table 4.3: Popular Operating Systems Cross All Three Spheres of Influence Principles of Information Systems, Seventh Edition

Current Operating Systems Microsoft PC operating systems Apple computer operating systems Linux Principles of Information Systems, Seventh Edition

Workgroup Operating Systems Windows Server UNIX NetWare RedHat Linux Mac OS X Server Principles of Information Systems, Seventh Edition

Enterprise Operating Systems z/OS MPE/iX and HP-UX Linux Principles of Information Systems, Seventh Edition

Operating Systems for Small Computers and Special-Purpose Devices Palm OS Windows Embedded Windows Mobile Principles of Information Systems, Seventh Edition

Utility Programs Utility programs are used to: Merge and sort sets of data Keep track of computer jobs being run Compress data files before they are stored or transmitted over a network Perform other important tasks Principles of Information Systems, Seventh Edition

Utility Programs (continued) Hardware utilities Virus-detection and virus-recovery utilities File-compression utilities Spam and pop-up blocker utilities Principles of Information Systems, Seventh Edition

Utility Programs (continued) Network and Internet utilities Server and mainframe utilities Other utilities Principles of Information Systems, Seventh Edition

Table 4.4: Examples of Utility Programs Principles of Information Systems, Seventh Edition

Application Software Primary function is to apply the power of the computer to give individuals, workgroups, and the entire enterprise the ability to solve problems and perform specific tasks Application programs interact with systems software; systems software then directs the computer hardware to perform the necessary tasks Principles of Information Systems, Seventh Edition

Types and Functions of Application Software Proprietary software: a one-of-a-kind program for a specific application, usually developed and owned by a single company Off-the-shelf software: existing software programs that are purchased Principles of Information Systems, Seventh Edition

Table 4.5: A Comparison of Proprietary and Off-the-Shelf Software Principles of Information Systems, Seventh Edition

Table 4.5: A Comparison of Proprietary and Off-the-Shelf Software (continued) Principles of Information Systems, Seventh Edition

Personal Application Software Serve the needs of an individual user Include personal productivity software, which enable users to improve their personal effectiveness Principles of Information Systems, Seventh Edition

Table 4.6: Examples of Personal Productivity Software Principles of Information Systems, Seventh Edition

Table 4.6: Examples of Personal Productivity Software (continued) Principles of Information Systems, Seventh Edition

Workgroup Application Software Workgroup application software: designed to support teamwork, whether people are in the same location or dispersed around the world Groupware: software that helps groups of people work together more efficiently and effectively Principles of Information Systems, Seventh Edition

Table 4.8: Ernst & Young’s “Three Cs” Rule for Groupware Principles of Information Systems, Seventh Edition

Enterprise Application Software Software that benefits an entire organization Enterprise resource planning (ERP) software: a set of integrated programs that manage a company’s vital business operations for an entire multisite, global organization Principles of Information Systems, Seventh Edition

Table 4.9: Examples of Enterprise Application Software Principles of Information Systems, Seventh Edition

Programming Languages Programming languages: sets of keywords, symbols, and a system of rules for constructing statements Allow humans to communicate instructions to be executed by a computer Different languages have different characteristics Syntax: a set of rules associated with a programming language Principles of Information Systems, Seventh Edition

Table 4.11: The Evolution of Programming Languages Principles of Information Systems, Seventh Edition

First Generation Machine language Required use of binary symbols (0s and 1s) Principles of Information Systems, Seventh Edition

Second Generation Assembly languages Use symbols rather than binary digits Assemblers: programs that translate assembly languages into machine code Principles of Information Systems, Seventh Edition

Third Generation Greater use of symbolic code Examples: BASIC, COBOL, C, and FORTRAN Compiler: a software program that converts the programmer’s source code into the machine-language instructions consisting of binary digits Principles of Information Systems, Seventh Edition

Figure 4.18: How a Compiler Works Principles of Information Systems, Seventh Edition

Fourth Generation 4GLs: fourth-generation languages Easier to use, and more English-like, than third generation languages Programs tell the CPU the desired results, not how to get them Examples: SQL, SAS Principles of Information Systems, Seventh Edition

Languages Beyond the Fourth Generation Artificial intelligence, visual, and object-oriented languages Easier for nonprogrammers to use Programming languages used to create artificial intelligence or expert systems applications are called fifth-generation languages (5GLs) Visual languages use a graphical or visual interface for program development Object-oriented programming languages are based on objects (data and the actions that can be performed on it) Principles of Information Systems, Seventh Edition

Software Issues and Trends Software bugs: defects in a computer program that keep it from performing in the manner intended Copyrights and licenses Open-source software: software that is freely available to anyone in a form that can be easily modified Principles of Information Systems, Seventh Edition

Software Issues and Trends (continued) Shareware and freeware: software that is very inexpensive or free, but whose source code cannot be modified Multiorganizational software development Software upgrades Global software support Principles of Information Systems, Seventh Edition

Summary Computer programs: sequences of instructions for the computer Systems software: coordinates the activities of hardware and programs Applications software: helps users solve particular problems Operating system (OS): a set of computer programs that controls the computer hardware and acts as an interface with application programs Principles of Information Systems, Seventh Edition

Summary (continued) Graphical user interface (GUI): a user interface that uses icons and menus displayed on screen to send commands to the computer system Time-sharing allows more than one person to use a computer system at the same time Proprietary software: a one-of-a-kind program designed for a specific application, usually developed and owned by a single company Off-the-shelf software: existing software program that is purchased Principles of Information Systems, Seventh Edition

Summary (continued) Enterprise resource planning (ERP) software: manages a company’s vital business operations for an entire multisite, global organization Programming languages allow humans to communicate instructions to be executed by a computer Programming languages can be classified as first generation, second generation, third generation, fourth generation, and languages beyond the fourth generation Principles of Information Systems, Seventh Edition