Usually the description of a system is given in natural language or in diagrams. It is very hard to make this kind of informal description clear, concise and unambiguous. Implementations based on informal specifications are usually prone to errors, omissions and incompatibilities. This paper presents an attempt to introduce Formal Description Techniques (FDT's), originally developed for the area of telecommunications and data transfer, as a mean for the specification/description of manufacturing systems. A brief introduction on standard FDT's, LOTOS, ESTELLE and SDL is given. Several concepts were behind the development of these techniques and this paper exploits the extended finite state machine (EFSM) concept as a suitable form for specification/description of manufacturing systems using FDT ESTELLE
