Computer Language Sequence of instructions written to perform a specified task for a computer. A computer requires programs to function, typically executing the program's instructions in a central processor.
Generations of programming languages.
First-Generation
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 An assembler converts the assembler language statements into machine language.
Third-generation
Language is a "high-level" programming language, such as PL/I, C, or Java. Java language statements look like this: public boolean handleEvent (Event evt) { switch (evt.id) { case Event.ACTION_EVENT: { if ("Try me" .equald(evt.arg)) { A compiler converts the statements of a specific high-level programming language into machine language. (In the case of Java, the output is called bytecode, which is converted into appropriate machine language by a Java virtual machine that runs as part of an operating system platform.) A 3GL language requires a considerable amount of programming knowledge.
Fourth-Generation
Language is designed to be closer to natural language than a 3GL language. Languages for accessing databases are often described as 4GLs. A 4GL language statement might look like this: EXTRACT ALL CUSTOMERS WHERE "PREVIOUS PURCHASES" TOTAL MORE THAN $1000 5GL or 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. Microsoft, Borland, IBM, and other companies make 5GL visual programming products for developing applications in Java, for example. Visual programming allows you to easily envision object-oriented programming class hierarchies and drag icons to assemble program components. 
