Mounir Khlat and Patrick Jeulin are the two co-author of these environment, even a lot of developers were involved in the GraphTalk project @ Xerox first and @ Parallax Software Technology after.
The previous implementation environment was the Xerox InterLispD on Xerox 1186 workstation and on Sun workstation with the InterLispD emulator.
Programming with GraphTalk is pure Visual programming, even APIs allow developers to implement sophisticated triggers, methods or modules.
After 1988, GraphTalk was completely re-designed and re-implemented in C/C++ to be running on OS2/Presentation Manager, Windows, Unix/Motif on Sun, HP and IBM workstations.
The main part of GraphTalk is the GraphTalk developer environment (Meta-tool) with dedicated graphs editors to specify the grammar of the editors. A compiler uses this source code to generate the CASE tool.
A CASE tool is an hypergraph editor, each graph has his own grammar.
GQL (GraphTalk Query Language) allows to access to all information in the hypergraph with a SQL like syntax.
Properties of each instance (hypergraph, graph, node, link) could be multi-valued typed field (integer, decimal, string, binary file, structured file, etc..), or other instances (graph, nodes).
GQLReport (a mixed of GQL and XML) allows to produce Word document instances of GTD (GraphTalk Template Documents).
With GraphTalk, a lot of CASE tools were implemented, directly by the Xerox and Parallax Software Technologies team, and by partners too (for exemple a fusion CASE tool by SoftCase?? in UK, or annOSSAD environment by C-Log in Switzerland).
The main devleopped CASE tool were: SADT, IDEF0, SA, SD, SART, Gane-Sarson, Merise, Merise2, Niam, Maia, Hood, OMT, UML, OOA Shlaer and Mellor, Axial.
Several models generator were developed by Leopold Wilhelm. The generation used GKnowledge (an inference engine developped with GraphTalk) to take as input for example a NIAM data model and to generate a 5th NF relational model with the complete integrity rules.
Some IT software engineering teams like [http://www.transferpod.com ipod to mac] developed their own modeling environments like the french Telco labs (CNET) with ASN1 generation, or Sextant Avionique for a test environment dedicated to the Dassault Rafale aircraft, with an Atlas code generator or ELF/Total for an upper-CASE to drive SAP applications integration thru a Gane Sarson DFD.
Some french universities used GraphTalk to develop some research prototypes.
Since 1995, GraphTalk is a product and a trademark of CSC (Computer Sciences Corporation)