DETAILED INSTRUCTIONS TO CONTROL COMPUTER OPERATION

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SOFTWARE

• DETAILED INSTRUCTIONS TO CONTROL COMPUTER
  OPERATION
• PROGRAM SET OF INSTRUCTIONS TO THE COMPUTER
• STORED PROGRAM MUST BE IN PRIMARY STORAGE
• SYSTEM SOFTWARE MANAGES COMPUTER RESOURCES
• APPLICATION SOFTWARE SPECIFIC BUSINESS
  APPLICATION

System SW, Application development SW,
Applications
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Computer Software
Computer Software
Performs information Processing tasks for End
users
Manages and supports Operations of
computer Systems and networks
Application Software
System Software
General purpose Application Programs
Application Specific Programs
System Management Programs
System Development Programs

• Web browsers
• E-mail
• Word processing
• Spreadsheets
• Presentation graphics
• Groupware

• ERP
• Business Apps
• E-Commerce
• Education
• Entertainment

• Operating systems
• Network management
• System utilities
• Performance monitors
• Security monitors

• Programming languages
• Application development

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SOFTWARE
Simultaneous Activities Priorities
APPLICATION SOFTWARE
SYSTEM SOFTWARE
HARDWARE
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MULTIPROGRAMMING
Concurrent use of CPU / execute until I/O rqst
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MULTITASKING

• MULTIPROGRAMMING
• ON A
• SINGLE-USER SYSTEM
• SUCH AS A
• MICROCOMPUTER

One person can run two or more programs or
tasks Concurrently. Multiple windows open. Could
not do this under DOS
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VIRTUAL STORAGE

• METHOD OF HANDLING SEVERAL PROGRAMS IN PRIMARY
  STORAGE
• PROGRAM DIVIDED INTO
• FIXED LENGTH PORTIONS (PAGES) OR
• VARIABLE LENGTH (SEGMENTS)
• CURRENT PORTIONS RESIDE IN PRIMARY STORAGE
• PORTIONS SWAPPED OUT WHEN DONE

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MULTIPROCESSING

• TWO OR MORE PARALLEL PROCESSORS IN SYSTEM
• PROGRAM CAN BE DIVIDED TO BE PROCESSED BY
  MULTIPLE CPUs
• CAN PROCESS LARGE PROGRAMS MORE RAPIDLY

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LANGUAGE TRANSLATION

• SOURCE CODE HIGH-LEVEL LANGUAGE INSTRUCTIONS
• COMPILER TRANSLATES HIGH-LEVEL CODE INTO MACHINE
  LANGUAGE
• OBJECT CODE TRANSLATED INSTRUCTIONS READY FOR
  COMPUTER

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TRANSLATION PROCESS
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MICROCOMPUTER OPERATING SYSTEMS
OPERATING SYSTEM
FEATURES

List example operating systems
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MICROCOMPUTER OPERATING SYSTEMS
OPERATING SYSTEM
FEATURES
Unix
For powerful Microcomputers, Workstations,
Minicomputers. Multitasking Multi-user
Processing Networking. Portable to various
Computer Platforms
Linux
Free, reliable alternative to Unix, Windows. Runs
on many Platforms
Mac OS
For Macintosh computers. Multitasking. Powerful
Graphics Multimedia
DOS
For IBM (PC-DOS) and PC (MS-DOS). Program
Memory 640K
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GENERATIONS OF PROGRAMMING LANGUAGES

• 1st. MACHINE LANGUAGE binary code
• 2nd. ASSEMBLY LANGUAGE mnemonics for numeric
  code
• 3rd. HIGH-LEVEL LANGUAGES written with regular
  words (fortran, cobol)
• 4th. MODERN APPLICATION PACKAGES

0s and 1s
Registers
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HIGH-LEVEL LANGUAGES

• FORTRAN (FORmula TRANslator) Scientific,
  Engineering applications
• COBOL (COmmon Business Oriented Language)
  Predominant for transaction processing
• BASIC (Beginners All-purpose Symbolic Instruction
  Code) General purpose PC language

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FOURTH GENERATION LANGUAGES (4GL)

• CAN BE EMPLOYED BY END USERS
• NONPROCEDURAL
• CAN DEVELOP APPLICATIONS QUICKLY
• NATURAL LANGUAGES
• SIX CATEGORIES

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FOURTH GENERATION LANGUAGES (4GL)

• 1. QUERY LANGUAGES
• rapidly retrieve data
• interactive/ on-line
• may use NATURAL LANGUAGE
• support special requests for data from
  relational databases

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FOURTH GENERATION LANGUAGES (4GL)

• 2. REPORT GENERATORS
• Create customized reports
• Wide range of formats
• 3. GRAPHICS LANGUAGES
• Can manipulate drawings, graphs, photos, videos
• Presentation managers

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FOURTH GENERATION LANGUAGES (4GL)

• 4. APPLICATION GENERATORS
• User specifies computer needs
• Generator creates logic and code for application
• Greatly reduces development time

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FOURTH GENERATION LANGUAGES (4GL)

• 7. SOFTWARE PACKAGE Commercially available set
  of programs...
• WORD PROCESSING
• SPREADSHEETS
• DATA MANAGEMENT
• PRESENTATION MANAGEMENT
• INTEGRATED SOFTWARE PACKAGES NOW COMBINE THESE
  TO SIMPLIFY LEARNING AND USE

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New Development Tools
Platform independent

• JAVA Sun Microsystems OBJECT-ORIENTED
  PROGRAMMING LANGUAGE (all appliances)
• APPLET TINY PROGRAM TO EXECUTE SMALL FUNCTION
  (Runs in browser)
• APPLETS DOWNLOADED FROM NETWORK
• RUN ON ANY COMPUTER OPERATING SYSTEM (in
  theory bull)
• Requires JVM part of web browser. Interprets
  each command. (runs in a sandbox
• Servlet Java program runs on server

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New Development Tools
HTML used to display a Web page and tells where
words should be Placed. (Hypertext markup
language) Interpreted by web browsers (IE and
Netscape) XML eXtensible Markup Language
describes the data DTD document type definition
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ASP Application Service Providers
Host application SW for other businesses, usually
over the Web.
ExpensAble.com (TE) travel and enter. expense
reporting SW via web. 5K one time fee and
5/user/month.
Advantages No need to maintain SW or HW Always
available Auto updates Browser is only SW required