Chapter 3 Software

1
Chapter 3Software

• Two major types of software
• 1. Application Software - Programs designed for a
  specific purpose
• 2. System Software - Programs that manage the
  resources and operations of the computer system

2
Software Trends

• The trend in software is moving away from
  customized software designed for a specific
  company or organization
• Getting away from symbolic code
• Moving away from procedural programming languages

3
Software Trends

• Trend is towards the use of pre-written
  off-the-shelf software
• Use of natural style languages
• Visual interface, Object Oriented

4
Reasons for Current Trends

• Software developers have assembled software
  suites that bundle several applications
  together
• Designed for ease of use and multiple functions
• Most recent trend is towards the offering of
  application software packages over the Internet

5
Application Software

• Two types of application software
• 1. General purpose - word processors,
  spreadsheets, database management programs,
  graphics, web browsers, email packages, groupware
• 2. Software suites combine several general
  purpose applications

6
The Suite Advantage

• Often called productivity suites
• Less expensive than separate purchases
• Most suites use a common graphical interface
  (same look , feel)
• Work together (import, export data)

7
Disadvantages of Suites

• Experts argue that most users never use the
  additional features
• Suites take up a lot of hard disk space and
  usually need high amounts of RAM
• Suites generally work slower than a stand alone
  application (because of integration)

8
Integrated Packages

• Integrated packages like Microsoft Works are a
  multifunction single application
• Disadvantage is the lack of features available in
  suites

9
Web Browsers

• Latest and greatest piece of application software
• Offer the ability to connect to the Internet and
  use Internet technology for additional purposes
• Fast becoming the universal piece of application
  software

10
Email Software

• Has changed the way people communicate
• Allows for messages to be sent to individual
  recipients or many at one time
• Can be secure message (password or encrypting)
• Allows for file attachment to message
• Can allow for remote access

11
Word Processors and Desktop Publishing

• Packages that allow for the creation, editing,
  revision, and printing of text based documents
• Can be converted easily to HTML format for web
  application
• Incorporate utilities such as grammar checkers,
  spelling checks, word usage, etc

12
Desktop Publishing

• Application software that allows for production
  of newsletters, books, manuals
• Allows for designing of page layout to work
  around non traditional page forms
• Allows for importing and formatting of images,
  graphics

13
Electronic Spreadsheets

• Program used for numerical analysis, planning,
  and modeling
• Can be used as database
• Very powerful business tool that can be easily
  customized by the end user

14
Database Management

• A database management application allows for the
  organized storage of data
• Allows for
• database development
• database interrogation (queries)
• database updates (acid functions)
• protection of data
• application development

15
Presentation Graphics

• Used to develop multimedia presentations
• Allow for the use of images, pictures, etc
• Easy to use
• Very effective teaching tool
• Can be used for web sites (must be transformed
  into HTML)

16
Hypermedia Technology

• Electronic documents that contain multiple forms
  of media
• Require use of specialized programming languages
  such as JAVA for development
• Creates links within HTML pages

17
Personal Information Managers

• Popular for end users
• Require no difficult programming
• Electronic calendar, appointment manager,
  schedule book
• Good for scheduling meetings within an
  organization
• May have an email link

18
Groupware

• Collaborative work software
• Central theme is to make group work possible and
  to remove barriers
• Allow for work folders where project documents
  are stored for access by project workers

19
System Software

• Manages the operation of the computer
• Link between hardware and application software
• Two main types of System Software
• System management
• System development

20
System ManagementSoftware

• Programs that manage hardware, software, and data
  resources of a system
• Four main types
• Operating systems
• Network management programs
• DBMS
• System Utilities

21
System DevelopmentSoftware

• Programs that aid in the development of custom
  software application
• Three basic forms
• Translators and compilers
• Programming tools
• CASE (computer assisted software engineering)

22
Operating System

• Single most important software package in a
  system
• Manages CPU
• Controls inputs, outputs, and system operation
• Directs system resources to maximize
• Allows for use of peripheral devices

23
Five Functions of Operating System

• Provides user interface
• Manages resources
• Manages tasks
• Manages files
• Provides for support (help screens) and utilities

24
User Interface

• Allows for communication and direction by the
  user to load programs, access and manage files
• Three main types
• Command driven
• Menu driven
• Graphical User Interface

25
User Interface

• The trend is towards graphical interfaces that
  make system commands appear simple

26
Resource Management

• The operating system controls programs that
  manage many system functions including
• CPU
• Memory
• Secondary storage
• I/O devices

27
File Management

• The operating system controls the creation,
  storage, accessing of and management of files in
  the system
• Keeps track of the physical location of files on
  disks and other secondary storage devices

28
Task Management

• The operating system allows the computer to
  accomplish multiple tasks seemingly at the same
  time
• Multitasking
• Time sharing

29
Popular Operating Systems

• MS-DOS
• Windows 95/98/2000
• Windows NT
• OS/2
• UNIX
• LINUX
• Macintosh 7

30
System Development Software

• Programs are instruction sets
• Programs are written in many different
  programming languages
• There has been a definite evolution in
  programming languages
• There are five main categories of programming
  languages

31
Machine Language

• Basic level of programming language
• Written using binary code
• Very complicated and time consuming
• Very error prone

32
Assembler Languages

• Second generation of programming languages
• Usually called Symbolic languages
• Simpler to write than machine code
• Had to be used with a particular machine

33
High-Level Languages

• Third generation language
• COBOL, BASIC, FORTRAN
• Easier to learn because of orientation towards
  natural language
• Machine independent
• Must be compiled or translated into machine code
  by the software

34
4GL

• More conversational than others
• Simplifies programming tasks
• Use nonprocedural language
• Natural language
• Somewhat less flexible than some languages

35
Object Oriented Languages

• Links data elements and procedures together
• Languages include Visual Basic, C, C, Java
• Easier to use
• Can use same object in multiple programs

36
HTML and Java

• HTML is a page defining language used for
  internet technology systems
• Java is an object oriented language
• Java was designed for real time uses
• Java code can contain small application programs
  within large programs called applets and/or
  JavaBeans

37
Language Translators

• Necessary to convert programming languages into
  machine code
• Assemblers - translate symbolic code
• Compilers - translate high level languages
• Interpreters - Execute instructions one level at
  a time