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Programming Language
Generations
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Topics
! Explain the five generations of programming languages
! Effects of computer technology evolution on the generations of programming languages
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Generations of Programming Languages
! Occurring in “generations” ! Levels range from machine languages to natural
languages ! Lower levels - closer to machine language,
closer to 0’s and 1’s ! Higher levels - closer to human-like language
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Generations of Languages
! 1st -- Machine languages
! 2nd -- Assembly languages
! 3rd -- High level procedural languages
! 4th -- Problem-oriented languages
! 5th -- Natural languages and visual
programming
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Generations of Languages
! First Generation: Machine languages - data represented in 1’s and 0’s
! Second Generation: Assembly languages - abbreviations and mnemonics replace the 0’s and 1’s
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Generations of Languages ! Third Generation: High level procedural
languages ! Express the logic for solving general problems ! Must translate procedural language into
machine language ! Compiler - Converts source code into object code
which is saved so it can be run later ! Interpreter - Converts one line of source code
into object code and executes it immediately - no object code is saved
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Third Generation: Procedural Languages
! Ada ! BASIC ! C/C++
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Third Generation: Procedural Languages (continued)
! COBOL (Business) ! FORTRAN-(Science) ! HTML ! Java ! Pascal
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Fourth Generation: Problem-Oriented Languages
! For solving specific problems ! Query languages ! Application generators
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Fourth Generation: Problem-Oriented Languages
! Specific problem-solving example ! Interactive Financial Planning System
! Query Languages ! Structured Query Language uses such commands as
SELECT, COMPARE, DISPLAY, UPDATE ! Application Generators
! Uses general task preprogrammed modules to generate code for a specific application
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Fifth Generation: Natural Languages
! Languages more like English, French, Japanese, etc. still being developed
! Intent to humanize the computer-person interface
! Hope to teach computers to learn
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! Application Service Providers (ASPs) ! Outsourcing programmers solving many difficulties
by providing custom solutions
! “Pay as you go” software
! Web-based applications ! In-House Programmers
! Maintenance problems still surface ! More Natural Language Programming
A Look to the Future
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Discussion Questions
! What are the five generation levels of programming languages?
! Describe the characteristics of the five generations of programming languages.
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Participation Question
Fifth-generation languages (5GL) possess which one of the following characteristics?
A. All code must be complied before use. B. Software code always uses a combination of
objects. C. Software code uses English words and
symbols. D. Software code is written using binary codes. E. Coding is done with assembly language.
