Generations of Computer Languages

1. First-Generation Language

1.1. -Also known as machine languages -First languages available for programming -Consists of a set of commands, represented as a series of 1s and 0s -Specific to a particular CPU or microprocessor family -Rarely used to write programs

2. Second-Generation Language

2.1. -Also known as assembly language -Allows programmers to use abbreviate commands words, called op codes such as LDA for load, rather than the 1s and 0s used in machine languages -Classified as a low-level language because it is machine specific -Useful when a programmer wants to directly manipulate what happens at the hardware level -Typically used to write system software such as compilers, operating system, and device drivers

3. Third-Generation Language

3.1. -When high-level languages were originally conceived in the 1950s, they were dubbed third-generation languages becaused they seemed a major improvement over machine and assembly languages -Use easy-to-remember command words, such as PRINT and INPUT, to take the place of several lines of assembly language op codes or lengthy strings of machine language 0s and 1s -Scientists believed that third-generation languages eliminated programming errors -Errors became less frequent and program development time decreased significantly -Third-generation languages, such as COBOL and Fortran were used extensively for business and scientific applications -Pascal and BASIC were popular teaching languages

4. Fourth-Generation Language

4.1. -In 1969, computer scientists began to develop high-level languages called fourth-generation languages -Closely resemble human languages or natural languages -Fourth-generation languages such as SQL and RPG, eliminate many of the strict punctuation and grammar rules that complicate third-generation languages -Typically used for database applications -A single command written in a fourth-generation language can replace many lines of third-generation code

5. Fifth-Generation Language

5.1. -Prolog and other declarative languages became closely indentified with the fifth-generation project and were classified by some experts as fifth-generation languages -Other experts disagree with this classification and instead define fifth-generation languages as those that allow programmers to use graphical or visual tools to construct programs, instead of typing lines of code