Evolution of programming languages

The desire to use the power of information processing efficiently in problem solving has pushed the development of newer programming languages. The evolution of programming languages is typically discussed in terms of generation of languages

First Generation

The first generation of programming languages is machine language, which required the use of binary symbols (0s and 1s). Because this is the language of the CPU, text translated into binary sets can be read by almost every computer system platform. Originally no translator was used to change the source code into object code.

econd Generation

Developers of programming languages attempted to overcome some of the difficulties inherent in machine language by replacing the binary digits with symbols that programmers could more easily understand. These second-generation languages use codes, like A for add, MCV for move and so on. Another term for these languages is assembly language, which comes from the programs (called assemblers) used to translate it into machine code. Systems software programs such as OSs and utility programs are often written in an assembly language.

Third Generation

Third-Generation languages continued the trend toward greater use of symbolic code and away from specifically instructing the computer how to complete an operation. BASIC, COBOL, C and FORTRAN are examples of third-generation languages that use English and Assembly languages because it more closely resembles everyday human communication and understanding.

With third-generation and higher-level programming languages, each statement in the languages translates into several instruction in machine language. A special software program called a compiler converts the programmers' s source code into the machine-languages instructions consisting of binary digits. A compiler creates a two-stage process for program execution. First, it translates the program into a machine language; second, the CPU executes that program. Another approach is to use an interpreter, which is a language translator that converts each statement in a programming language into machine language and executes the statement, one at a time. An interpreter does not produce a complete machine-language program. After the statement executes, the machine-language statement is discarded, the process continues for the next statement, and so on.

Fourth Generation

Fourth-generation programming languages emphasize what output results are desired rather than how programming statements are to be written. As a result ,many managers and executives with little or no training in computers and programming are using fourth-generation languages (4GLs). Languages for accessing information in a database are often fourth-generation languages. Prime examples include PowerBuilder, Delphi, Essbase, Forte, Focus, Powerhouse, SAS, and many other. Natural is a 4GL that can be used with Windows, UNIX, or Linux. Another popular fourth-generation languages is called Structured Query Language (SQL), which is often used to perform database queries and manipulations.