Introduction to Computer Software PDF

Introduction to Computer Software Chapter 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...

Introduction to Computer Software Chapter 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. Outline the functions of an operating system. Describe the main uses of high-level, fourth- generation, object-oriented, and Web-oriented programming languages and tools. Categories of Computer Software Computer Software Application System Software Software General- Application- System System Purpose Specific Management Development Programs Programs Programs Programs Categories of Computer Software Information systems depend on software resources to help end users use computer hardware to transform data into information products. Software handles the input, processing, output, storage, and control activities of information systems. Computer software is typically classified into two major types of programs: Categories of Computer Software Systems Software. These are programs that manage and support the resources and operations of a computer system. – System Management Programs. These programs help run the hardware and communicate critical information throughout the IS. Examples are operating systems, operating environments (such as GUI interfaces), database management systems, and telecommunications monitors. – System Development Programs. These programs are used to build new application programs or specific information systems applications. Examples include programming language translators, programming environments, and CASE packages. Categories of Computer Software Applications Software. These are programs that direct the performance of a particular use, or application, of computers to develop specific information products by end users. – General-Purpose Application Programs. These programs allow end users to create a great many different information products within a general knowledge category. Examples include word processing, spreadsheets, database managers, graphics, and integrated packages. – Application-Specific Programs. These programs are dedicated to very specific functions within a knowledge area. Examples include programs for accounting, generating marketing plans, or handling financing. Trends in Computer Software First Second Third Fourth Fifth Generation Generation Generation Generation Generation Trend: Toward Easy-to-Use Multipurpose Network-Enabled Application Packages for Productivity and Collaboration Natural & Object-Oriented DBMS Languages User-Written Packaged Operating Fourth-Generation Multipurpose Programs Programs Systems Languages Graphic- Interface Machine Symbolic High-Level Microcomputer Network-Enabled Languages Languages Languages Packages Expert-Assisted Packages Trend: Toward Visual or Conversational Programming Languages and Tools Common General- Purpose Applications Electronic Mail Word Processing Presentation Graphics Multimedia Personal Information Manager Groupware Common General- Purpose Applications There are numerous general-purpose application programs commonly used in business. These include: Electronic Mail. Communication software that allows you to send electronic messages via the Internet or an intranet. Examples: Eudora, Webmail. Word Processing Programs. Are programs that computerize the creation, editing, and printing of documents. Examples: Microsoft Word, Corel WordPerfect. Electronic Spreadsheet. Software that helps you to design and create electronic accounting spreadsheets for use in business analysis, planning, and modeling. Examples: Lotus 1-2-3, Microsoft Excel. Common General- Purpose Applications Presentation Graphics. Software that helps you prepare multimedia presentations of graphics, animations, video clips etc., as well web pages. Examples: Microsoft PowerPoint, Lotus Freelance. Multimedia Software. Related to presentation software is multimedia software. This software is used to create a wide variety of presentation products, information products, education and entertainment products, and usually comes with tools specifically created to capture and edit various types of media, e.g. video, audio, animation etc. Examples: Corel Draw 9, Adobe PhotoShop, Macromedia, Shockwave. Common General- Purpose Applications Personal Information Managers. Software that helps end users store, organize, and retrieve information like schedules and management appointments, meetings, customers and clients etc. Examples: Lotus Organizer, Microsoft Outlook. Groupware Software. Collaboration software that helps workgroups and teams work together to accomplish group assignments. Examples: Lotus Notes, Microsoft Exchange. Web Browsers Launch Discussion Surf the Net Information Groups Searches Typical uses of a Web Browser in Internet, Intranet, and Extranet Environments Multimedia File E-Mail Transfer Web Browsers Let’s take a moment to examine a couple of other important types of application software in some more detail. Web Browser: The most important software component for many computer users today is the powerful and feature-rich web browser. A browser is a key software interface you use to point and click your way through the hyperlinked resources of the World Wide Web and the rest of the Internet, as well as corporate intranets and extranets. Two popular browsers include: Netscape Navigator, Microsoft Explorer. Web Browsers Web Browser as the Universal Client: Industry experts are predicting that the web browser will be the model for how most people will use networked computers into the next century. Browsers are being called the universal client, that is, the software component installed on the workstation of all the clients (users) in client/server networks throughout an enterprise. Web browsers have evolved into suites of communication and collaboration software including: discussion forums, databases, audio and data conferencing, chat, Internet telephone, group scheduling, calendaring, and web page editor. Database Management Packages Database Database Development Interrogation Primary Tasks of Database Management Packages Database Application Maintenance Development Database Management Packages Database and graphics programs are also increasingly common in the business environment. Together with word processing and spreadsheet programs, they are often combined in integrated software packages designed to work together as an "Office Suite." Database Management Programs. These packages allow end users to set up database files and records on their personal computers. Most DBMS packages perform four primary tasks: Database Development. This defines and organizes the content, relationships, and structure of the data needed to build a database. Database Interrogation. This provides access to the data for information retrieval and report generation. Database Management Packages Database Maintenance. This gives users the ability to add, delete, update, correct, and protect that data in the database. Application Development. This allows users to develop prototypes of data entry screens, queries, forms, reports, and labels for a proposed application. Multimedia Technologies Video Capture Authoring Card Language Compact Disk Storyboard Interactive Key Sound Board Technologies Compressed Audio of Multimedia Computer MIDI Edit System Interactive Digital Audio Video Digital Video Interactive Multimedia Technologies Multimedia refers to computer-based integration of a large amount of high-quality data and information sources focused on providing end users alternatives in the way they acquire, use, and take advantage of the information products or content of the multimedia package. Multimedia can be used to enhance and accelerate learning and is becoming the area of first choice in developing new business training packages. Key technologies include: Authoring Language: This is a high-level programming facility with English language commands. Compact Disk Interactive: This is a standard proposed by Philips Corp. for reading data from a CD-ROM disk. Multimedia Technologies Compressed Audio: This is designed to increase the storage capacity of disk systems. Computer Edit System: This is a video editing system controlled by computer to enhance accuracy and quality in frame-by-frame editing. Digital Audio: This is a technique for storing analog audio as a series of numbers. Digital Video Interactive: This compresses video images up to 160 to 1, necessary due to the very large sizes of digitized video data. Interactive Video: This allows the user to control the sequence of events unfolding on a video screen through manipulation of computer-based commands. Multimedia Technologies Musical Instrument Digital Interface (MIDI): This is the serial data transmission protocol for transporting musical information between compatible electronic musical devices. Sound Board: This is a circuit board and software that captures and plays back a sound on a PC. Storyboard: This is a visualization of a piece of multimedia “code” representing how the program will proceed, using frames from a sequence to show a visual skeleton of the piece. Video Capture Card: This circuit board and software allows end users to digitize analog video from a number of external devices such as TVs, VCRs, 8mm cameras, or still cameras. Business Enterprise Application Software Accounting and Financial Management Customer Supply Relationship Business Chain Management Decision Management Support Human Enterprise Resource Resource Management Planning Business Enterprise Application Software Business Enterprise Application Software are application packages that support managerial decision making and operational users. Such applications include these shown. Most of these will be discussed in more detail in later chapters. Enterprise Resource Planning (ERP). Uses integrated cross-functional software to reengineer, integrate, and automate the basic business processes of a company to improve its efficiency, agility, and profitability. Customer Relationship Management (CRM). These systems consist of a family of software modules that perform the business activities involved in such ‘front office’ processes like customer sales, marketing, and service. These tools enable companies to identify, target, Business Enterprise Application Software Human Resource Management. These are information systems that support human resource management activities such as recruitment, selection and hiring, job placement, performance appraisals and training and development. Accounting and Financial Management. These are information systems that record and report business transactions, the flow of funds through an organization, and produce financial statements. Thus, these systems provide information for the planning and control of business operations, as well as for legal and historical record keeping. Business Enterprise Application Software Supply Chain Management. A supply chain is the network of business processes and interrelationships among businesses that are needed to build, sell, and deliver a product to its final customer. Supply Chain Management applications integrate management practices and IT to optimize information and product flows among these processes and partners. Functions of an Operating System User Interface Utilities Resource Task File and Other Management Management Management Functions Functions of an Operating System The operating system of a computer manages the operations of the CPU, controls the input/output and storage resources and activities of the computer system, and provides various support services as the computer executes the application programs of users. The user interface is the part of the operating system that allows users to communicate with the computer. Interfaces can be command-driven (the user types in command instructions through the keyboard), menu- driven (the user selects commands presented on-screen with either a mouse or keyboard), and graphical (the user selects commands that appear as icons, buttons, bars, and other images with a mouse or other pointing device). Functions of an Operating System Through the interface, the end user has access to the following resources: – Resource Management. These programs manage the hardware of a computer system, including its CPU, memory, secondary storage devices, and input/output peripherals. – File Management. Operating systems also contain file management programs that control the creation, deletion, and access to files of data and programs. File management involves keeping track of the physical location of files on magnetic disks and other secondary storage devices. Functions of an Operating System – Task Management. Task management programs manage the computing tasks of end users. They give slices of the CPU's processing time to tasks and determine the logistics of which tasks take priority over others when more processing time is required. – Utilities and Other Functions. Operating systems may contain additional programs (or support for them to be added later) called utilities that help maintain the integrity of the system and its interface with the system hardware. Common utilities are used to defrag a system's hard drive, compress the space programs and files need for storage, or other functions. – Discussion topic: Discuss the advantages and disadvantages of popular operating systems, e.g. Windows 2000, UNIX, LINUX, Netware, etc. Categories of Programming Languages Machine Languages High Level Languages Markup Languages Use binary coded Use brief statements Use embedded instructions control codes 1001 1001 Compute X = Y + Z First heading 1100 1101 Assembler Languages Fourth Generation Object-Oriented Use symbolic coded Languages Languages instructions Use natural statements Define objects that contain data and actions LOD Y SUM THE FOLLOWING NUMBERS Document.write ADD Z (“Hi There”) Categories of Programming Languages A programming language allows a programmer or end user to develop the set of instructions that constitute a computer program. Each programming language has its own unique vocabulary, grammar, and uses. The major categories of programming languages are: Machine Languages. Machine languages (or first-generation languages) are the most basic level of programming languages. These use binary codes unique to the computer, requiring programmers to have a detailed knowledge of the specific CPU they wish to write software for. Assembler Languages. Assembler languages (or second- generation languages) reduce the difficulties in writing language code by using translator programs (assemblers) that convert the symbolic language of the code into machine language. Categories of Programming Languages High-Level Languages. High-level languages (or third- generation languages) use instructions, called statements that closely resemble human language or the standard notation of mathematics. They are translated into machine language by compilers or interpreters. Fourth-Generation Languages. Fourth-generation languages describe a variety of programming languages that are more nonprocedural and conversational than previous languages. Nonprocedural languages have programmers specify the results they want while the program works with the computer to determine the sequence of instructions that will accomplish those results. Categories of Programming Languages Object-Oriented Languages. Object-oriented programming (OOP) ties data and instructions together into objects that can be combined in many different ways with other objects to create programs. Unlike procedural languages, OO systems objects tell other objects to perform actions on themselves. Thus, objects are more efficient and can be reused to create new programs. Java is an example of an OOP, which is specifically designed for real-time, interactive, web-based network applications. What makes Java so special is that it is computing platform independent. This means that any computer and any operating system anywhere in a network can execute Java programs. HTML. Is a page description language that creates hypertext or hypermedia web documents. HTML embeds control codes, or tags, in the ASCII text of a document. These tags are used to designate titles, headings, graphics, multimedia components, as well as hyperlinks within the document. Categories of Programming Languages XML. Unlike HTML, XML describes the content of web pages by applying identifying tags or contextual labels to the data in web documents. By classifying data in this way, an XML website's information is more searchable, sortable, and easier to analyze. Programming Language Translation Compiler Interpreter Assembler IF A := B THEN Language 1001101 Translator 1110101 Program 0010110 Source Program Written in BASIC, COBOL, Language etc. Translation Machine Process Language Object Program Programming Language Translation Programming packages help programmers develop computer programs. These include: Language Translator Programs. These translate a set of instructions into the computer’s own machine language. Typical language translator programs include: Assembler. An assembler translates the symbolic instruction codes of programs written in an assembler language into machine language. Compiler. A compiler translates high-level language statements. Interpreter. An interpreter is a special kind of compiler that translates and executes each program statement one at a time. Programming Tools. Common programming tools include graphics-oriented editors and debuggers to help identify and avoid errors while programming. Chapter Summary Computer software consists of two major types of programs: application software that directs the performance of a particular end user task, and system software that controls and supports the operations of a computer system. Application software includes a variety of programs that can be segregated into general-purpose and application-specific categories. System software can be subdivided into system management programs and system development programs. The former is used to manage hardware, software, networks, and data resources. The latter is used by IS specialists to develop computer programs. Chapter Summary (cont) An operating system is an integrated system of programs that supervises the operations of the CPU. There are 5 major levels of programming languages. Language translator programs convert programming language instructions into machine language instructions.