Chapter 4 Computer Software McGraw-Hill/Irwin Copyright © 2011 by The McGraw-Hill Companies, Inc. All rights reserved.

Learning Objectives Describe several important trends occurring in computer software. Give examples of several major types of application and system software. Explain the purpose of several popular software packages for end user productivity and collaborative computing.

Define and describe the functions of an operating system. Learning Objectives Define and describe the functions of an operating system. Describe the main uses of computer programming software, tools, and languages. Describe the issues associated with open-source software. 4-3

Combine functions of several programs Advantages Integrated Packages Combine functions of several programs Examples: Microsoft Works, AppleWorks Advantages Lower price Less disk space Pre-installed on microcomputers Disadvantages Limited functionality

Collaborate on group assignments Groupware Collaborate on group assignments E-mail, discussion groups, databases, video conferencing Lotus Notes Novell GroupWise Microsoft Exchange Some allow teams to create websites Windows SharePoint Services, WebSphere

Software Alternatives Outsourcing Domestic Offshore Application service providers (ASPs) Companies that own, operate, and maintain application software and computer system resources Use the application for a fee over the Internet Pay-as-you-go Use expected to accelerate Outsourcing = contract programmers

Software Alternatives Cloud computing – services over the internet Natural step from grid computing (Chapter 3) Applications Virtualized hardware resources Vendors of cloud services SAP Business ByDesign, Salesforce.com, Google Apps, MidlandHR’s “iTrent as a Service” Advantages Low barrier to entry Cost Savings More powerful software Cloud computing is a style of computing in which software and, in some cases, virtualized hardware resources are provided as a service over the Internet. Users need not have knowledge of, expertise in, or control over the technology infrastructure “in the cloud” that supports them.

Categories of Group Software System Management Programs Manage the resources of a computer system Examples: Operating systems Network management programs Database management systems System utilities System Development Programs Helps develop IS programs and procedures and then prepare them for processing Language translators and editors CASE and programming tools System Management Programs Hardware Software Network Data resources Examples: Operating systems Network management programs Database management systems System utilities System Development Programs Helps users develop IS programs and procedures and then prepare them for processing Language translators and editors CASE and programming tools

Integrated system of programs that… Operating Systems Integrated system of programs that… Provides interface between user and computer Manages the operations of the CPU Controls the input/output, storage resources, and activities of the computer system Provides support for application programs Loaded first before other tasks

Popular Operating Systems Windows GUI, multitasking, networking, multimedia Microsoft’s operating system NT, XP, 2003, Vista, Windows 7 Different versions manage servers Windows Server 2008 Based on Vista Release 2 to correct performance and security issues Microsoft’s primary stated objective with Vista, however, was to improve the state of security in the Windows operating system. One of the most common criticisms of Windows XP and its predecessors has been their commonly exploited security vulnerabilities and overall susceptibility to malware, viruses, and buffer overflows. In light of these complaints, then-Microsoft chairman Bill Gates announced in early 2002 a companywide “Trustworthy Computing Initiative” to incorporate security work into every aspect of software development at the company. Microsoft claimed that it prioritized improving the security of Windows XP and Windows Server 2003 rather than finishing Windows Vista, significantly delaying its completion. In 2009, Microsoft released their newest operating system, Windows 7. Unlike its predecessor, Vista, which introduced a large number of new features, Windows 7 was intended to be a more focused and incremental upgrade with the goal of being fully compatible with applications and hardware with which Vista was already compatible. Windows 7 has been very well received and is rapidly replacing the installed base of Vista without receiving any of the complaints and struggles encountered by Vista adopters and users.

Popular Operating Systems Unix AT&T Multitasking, multi-user, network-managing Portable across computer sizes Linux Low-cost, powerful, reliable Similar to Unix-like Open-source Flexible Multiple machines

Open-Source Licensing Characteristics The Program Must allow distribution of Source code Compiled form The License Shall not restrict selling or giving away Must allow modifications Must allow distribution May restrict modified source code Must not discriminate Must not restrict other software distributed along with the licensed software The Program Must include source code and allow distribution in source code as well as compiled form The License Shall not restrict any party from selling or giving away the software as a component of an aggregate software distribution containing programs from several sources Must allow modifications and derived works, and must allow them to be distributed under the same terms as the license of the original software

Application virtualization Allows software to run on a different operating system. Advantages One machine acts like multiple machines Reduces the number of computers needed Energy savings Use software from multiple vendors Application virtualization software rapidly blurring the boundaries between machines and operating systems and operating systems and applications. Add this to the cloud computing concept and we have the makings of an anytime, anywhere, any machine, any application world.

JEE6 – Java Enterprise Edition 6 Microsoft .NET Web Languages HTML Hypertext documents for the Web XML Identifying tags or contextual labels Digital publishing Cheaper, faster Java Object-oriented Simple, secure, and platform independent Java applets on any computer JEE6 – Java Enterprise Edition 6 Microsoft .NET Web services are software components that are Based on framework of Web and object-oriented standards and technology Used to link the applications of different users and computing platforms via the Web Microsoft .NET is a relatively new collection of programming support for what are known as Web services, the ability to use the Web rather than your own computer for various services. Microsoft's .NET platform is expected to allow the entire range of computing devices to work together to update and synchronize user information and access to products and services from a starting point.

Help identify and minimize errors Programming Tools Help identify and minimize errors Graphical programming interfaces Programming editors Debuggers CASE Tools Help in the software development process. Combine many programming tools into a single application with a common interface Used in different stages of the systems development process