What is Fourth Generation Programming Language?

The language which is used to create programs is called a programming language. It comprises a set of instructions that are used to produce various kinds of output.

A Fourth Generation (Programming) Language (4GL) is a grouping of programming languages that attempt to get closer than 3GLs to human language, a form of thinking, and conceptualization and are easier to use than 3GLs. It is a non-procedural language which means that the programmer defines what has to be done instead of how the task is to be completed.I4GL is more familiar and similar to human language. A compiler translates the whole program once i.e. it generates the object code for the program along with the list of errors. The execution is very fast. It allows users to develop software. These languages are usually designed for specific purposes and are commonly used in database programming and scripts such as PHP, Python, SQL, and many more. 4GLs make programming easier, more efficient, and more effective for users with less programming skills.

4th generation language is also known as a domain-specific language or a high-productivity language.

Components of Fourth Generation:

The following are the components of 4GL:

Databases and tables: The Database and the tables on which the 4GL programs operate.
Form: The screen that is displayed for the user data entry. The source code for forms is kept in operating system files with a .per suffix and contains instructions for how 4GL is to format the screen. For a form available to a 4GL program, it must be compiled into a file with a .frm suffix. The 4GL programs in turn reference the fields on the compiled screens.
Module: Operating System files that contain the source code to your programs- a set of functions written in INFORMIX-4GL. These files have a suffix of .4gl and contain one or more components.
Main Function: Each executable Informix program has the MAIN function; it is the first thing that is executed and in turn calls other functions.
Function: Portions of 4GL programs that can be called from MAIN and other functions. These start with the FUNCTION keyword.
Reports: Portions of 4GL programs that create reports. They include headers, groupings, sorting, and more. They start with the FUNCTION keyword.
Programs: This is what is actually executed by the users. Depending on the 4GL product that you have (compiled or interpreted “Executable and Interpreted 4GL”), this file is executed either by the operating system or through a 4GL interpreter.