from
The Free On-line Dictionary of Computing (8 July 2008)
fourth generation language
4GL
<language> (4GL, or "report generator language") An
"application specific" language, one with built-in knowledge
of an {application domain}, in the way that {SQL} has built-in
knowledge of the {relational} database domain.
The term was invented by Jim Martin to refer to
{non-procedural} {high level languages} built around
{database} systems.
Fourth generation languages are close to {natural language}
and were built with the concept that certain applications
could be generalised by adding limited programming ability to
them.
When given a description of the data format and the report to
generate, a 4GL system produces {COBOL} (or other 3GL) code,
that actually reads and processes the data and formats the
results.
Some examples of 4GL are: {database query language} e.g.{SQL};
{Focus}, {Metafont}, {PostScript}, {S}, {IDL-PV}, {WAVE},
{Gauss}, {Mathematica}, and {data-stream languages} such as
{AVS}, {APE}, {Iris Explorer}.
(2004-04-01)