Fourth generation programming Languages
Introduction to Fourth generation programming Languages
A fourth-generation programming language (1970s-1990) (abbreviated 4GL) is a programming language or programming environment designed with a specific purpose in mind, such as the development of commercial business software. In the history of computer science, the 4GL followed the 3GL in an upward trend toward higher abstraction and statement power. The 4GL was followed by efforts to define and use a 5GL.
4GLs are closer to human language than other high-level languages and are accessible to people without formal training as programmers. They allow multiple common operations to be performed with a single programmer-entered command. They are intended to be easier for users than machine languages (first-generation), assembly languages (second-generation), and older high-level languages (third-generation).
In the computer industry, these abbreviations are widely used to represent major steps or "generations" in the evolution of programming languages.
First-generation language was (and still is) machine language or the level of instructions and data that the processor is actually given to work on (which in conventional computers is a string of 0s and 1s).
Second-generation language is assembler (sometimes called "assembly") language. A typical 2GL instruction looks like this: ADD 12,8
Third-generation language is a "high-level" programming language, such as PL/I, C, or Java.
fourth-generation language is designed to be closer to natural language than a 3GL language. Languages for accessing databases are often described as 4GLs.
Fifth-generation language is programming that uses a visual or graphical development interface to create source language that is usually compiled with a 3GL or 4GL language compiler.
List of Fouth generation programming Languages
4GLs are more programmer-friendly and enhance programming efficiency with usage of English-like words and phrases, and when appropriate, the use of icons, graphical interfaces and symbolical representations. The key to the realization of efficiency with 4GLs lies in an appropriate match between the tool and the application domain. Additionally, 4GLs have widened the population of professionals able to engage in software development.
- Visual FoxPro
- Visual DataFlex