Specification and Description Language (SDL) is a specification language targeted at the unambiguous specification and description of the behaviour of reactive and distributed systems. It is defined by the ITU-T (Recommendation Z.100.) Originally focused on telecommunication systems, its current areas of application include process control and real-time applications in general. SDL provides both a graphical Graphic Representation (SDL/GR)... preview: http://en.wikipedia.org/wiki/Specification_and_Description_Language 10/11/2006