COMPUTER SOFTWAREUnit -3 By : Smita Agarwal

COMPUTER SOFTWARE Introduction to Software System Software Business Application Software Programming Languages Assemblers, Interpreters and Compilers Software suites and Integrated Package

Text Book : Introduction to Information Technology - Turban, Rainer

and Potter, Chapter -4

INTRODUCTION TO SOFTWAREPart-1

INTRODUCTION Computer software, or just software, is a

collection of computer programs and related data that provide the instructions for telling a computer what to do and how to do it. 

Computer program: The sequences of instructions for the computer.

Software Development: The process of building software applications. It is slow, complex and error prone.

80% of IT personnel maintain existing software and 20% develop new application.

SOFTWARE CRISIS Software development process is slow,

complex and error prone. It gets more expensive as the complexity in

the software grows . The organizations are not able to develop

new software applications fast enough to keep up with rapidly changing business conditions and rapidly evolving technologies.

SOFTWARE FUNDAMENTALS The process of writing programs is called

Programming The individuals who perform this task are

called Programmers Stored Program Concept. Modern

hardware architecture in which stored software programs are accessed and their instructions are executed (followed) in the computer’s CPU, one after another.

Documentation. Written description of the functions of a software program

System Software: The class of computer instruction that serve primarily as an intermediary between computer hardware and application programs; provides important self-regulatory functions for computer systems.

Application Software: The class of computer instructions that direct a computer system to perform specific processing activities and provide functionality for users. Its primarily to manipulate data or text to produce or provide information.

DIFFERENT TYPES OF SOFTWARE:

SYSTEM SOFTWAREPart -2

SYSTEMS SOFTWARE The class of computer instruction that serve

primarily as an intermediary between computer hardware and application programs; provides important self-regulatory functions for computer systems.

System Software is the class of programs that Control and support computer hardware Facilitates programming , testing and debugging Support application software

System Software is grouped into two categories System Control Programs System Support Programs

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System control programs: Software programs that controls the use of the hardware, software, and data resources of a computer system.Operating system: The main

system control program, which supervises the overall operations of the computer, allocates CPU time and main memory to programs, and provides an interface between the user and the hardware.

SYSTEM CONTROL PROGRAMS

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SYSTEM SUPPORT PROGRAMSSystem support programs:

Software that supports the operations, management and users of a computer system by providing a variety of support services. Examples include System utility programsPerformance monitors, and Security monitors

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SYSTEM SUPPORT PROGRAMS System utilities: Programs that accomplish

common tasks such as sorting records, locating files, creating directories and sub- directories and managing memory usage.

System performance monitors: Programs that monitor the processing of jobs on a computer system and monitor system performance in areas such as processor time, memory space and application programs.

System security monitors: Programs that monitor a computer system to protect it and its resources form unauthorized use, fraud or destruction.

APPLICATION SOFTWAREPart-3

APPLICATION SOFTWARE The class of computer instructions that

direct a computer system to perform specific processing activities and provide functionality for users. Its primarily to manipulate data or text to produce or provide information.

Types of Application Software are :Proprietary application software /

Contract softwareOff-the-shelf application software /

Package

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APPLICATION SOFTWARE Proprietary application software. Software that

addresses a specific or unique business need for a company ; may be developed in-house or may be commissioned from a software vendor. Such specific software programs developed for a particular company by a vendor are called contract software.

Off-the-shelf application software. Software purchased, leased, or rented from a vendor that develops programs and sell them to many organizations; can be standard customizable. Package is a commonly used term for a computer program (or group of programs) that have been developed by a vendor and is available for purchase in a prepackaged form.

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TYPES OF PERSONAL APPLICATION SOFTWARE Personal application software is general-

purpose, off-the-shelf application programs that support general types of processing (e.g. Microsoft Office).

Nine Types of Personal Application software1. Spreadsheets 2. Data Management3. Word Processing 4. Graphics5. Desktop Publishing6. Multimedia 7. Communications8. Speech recognition Software9. Groupware

1. SPREADSHEETS Spreadsheets. Software that uses a

grid of coded rows and columns to display numeric or textual data in cells (e.g. Microsoft Excel, Lotus 1-2-3). Macros : Sequences of commands

used in spreadsheet software that can be executed with just one simple instruction

Integrated packages. Spreadsheet packages that offer data management and graphical capabilities in addition to regular spreadsheet functionality.

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2. DATA MANAGEMENT Data Management Software that

supports the storage, retrieval, and manipulation of related data.

Simple Filling Program – traditional manual data filing programs

Database Management Programs – Fast and Accurate programs with ability to store and retrieve data in primary and secondary storage. E.g : Ms - Access

3. WORD PROCESSING Software that allows the user to manipulate

text using many writing and editing features (e.g. Notepad, Word Pad, Microsoft Word). It can include: Editor program Formatting program Print program Dictionary Thesaurus Grammar checker Mailing List Program Integrated graphics, Charting and Drawing

Programs.

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4. GRAPHICS SOFTWARESoftware that enable the user to create, store, and display or print charts, graphs, maps, and drawings.

Presentation graphic software. Software that enables users to create graphically rich presentations by “pasting” graphic images into a textual presentation (e.g. Microsoft PowerPoint).

Analysis graphic software. Software that provides the ability to convert previously analyzed data into graphic formats (e.g. bar charts, pie charts).

Computer-aided Design (CAD) Software allows designers to design and build production prototypes in software, test them, compile parts lists, out-line assembly procedures, and then transmit the final design directly to machines

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5. DESKTOP PUBLISHING SOFTWARE.Software that enables user to combine photographs and graphic images with text, to produce a finished, camera ready document for newsletter , advertisement , announcement etc. E.g. :MS-Publisher

6. MULTIMEDIA SOFTWARE.Software that combines spatially based media (text and images) with time based media ( sound and video) for input or output of data.

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7. COMMUNICATIONS SOFTWARESoftware that allows computers, wherever they are located, to exchange data via cables, telephone lines, satellite relay systems, or microwave circuits. E.g. : E- Mail like MS -Outlook, Video conferencing Software like Skype

8. SPEECH-RECOGNITION SOFTWARE Software that recognizes and

interprets human speech, either one word at a time (discrete speech) or in a stream (continuous speech)Discrete speech Recognition- Can

interpret only one word at a time. User must pause between the words. It is used to control PC Software using words like Print, Execute .

Continuous speech Recognition- can interpret the continuous stream of words. Software must understand the context of a word and must overcome accent.

EXAMPLE: Handling calls with speech recognition.

JetAir Belgium (jetair.be), a travel company, handles 3,000 calls a day from 2,000 travel agents. Before installing its voice- recognition system, JetAir lost 20 percent of its calls, because operators were busy or the calls were too complicated for tone-activated voice mail. The speech-recognition system recognizes both Flemish and French among 13 supported languages. In addition to retaining the lost calls, JetAir estimates that it handles 150 extra calls daily, worth up to $25 million in annual revenue

9. GROUPWARE Software that facilitate communication, coordination, and

collaboration among people. It allows workgroups—people who need to interact with

one another within an organization— to communicate and share information, even when they are working together at a distance.

Groupware can provide many benefits to businesses, including more efficient and effective project management, location independence, increased communications capability, increased information availability, and improved workflow

E.g. : IBM’s Lotus Notes/Domino, is a document-management system, a distributed client/server database, and a basis for intranet and electronic commerce systems, as well as a communication support tool. This class of groupware supplements real-time communications with asynchronous electronic connections

SOFTWARE SUITES Software suites are collections of application

software packages that integrate some or all of the nine functions of the packages.

Software suites can include word processors, spreadsheets, database management systems, graphics programs, communications tools, and other applications. Microsoft Office, Novell Perfect Office, and Lotus SmartSuite are widely used software suites for PCs.

Copyright 2007 John Wiley & Sons, Inc. Technology Guide 2 27

SOFTWARE ISSUES Software defects Alien software Software evaluation and selection Software licensing Software upgrades Open systems Open source software