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Fourth generation Language

A fourth generation (programming) language (4GL) is a grouping of programming languages that attempt to get closer than 3GLs to human language, form of thinking and conceptualization.

4GLs are designed to reduce the overall time, effort and cost of software development. The main domains and families of 4GLs are: database queries, report generators, data manipulation, analysis and reporting, screen painters and generators, GUI creators, mathematical optimization, web development and general purpose languages.

Also known as a 4th generation language, a domain specific language, or a high productivity language
Advantages:
1. Simplified the programming process.
2. Use nonprocedural languages that encourage users and programmers to specify the results they want, while the computers determines the sequence of instructions that will accomplish those results.
3. Use natural languages that impose no rigid grammatical rules

Disadvantages:
1. Less flexible that other languages
2. Programs written in 4GLs are generally far less efficient during program execution that programs in high-level languages. Therefore, their use is limited to projects that do not call for such efficiency.

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