EA MDGs (“Model Driven Generation”) are the way that Sparx implement new modeling languages.
To do this, they follow the way that UML (Unified Modeling Language – the basis of most of what EA does) describes how to make new languages. It does this with a set of rules and structures, that describe what links of ‘thing’ a user can create using the new language, and how those things can be connected and drawn on diagrams.
Sparx EA has lots of free and paid-for MDGs, for different modeling languages, and some are built-in to the EA product.
The capabilities of EA MDGs and Model Expert Reference Models are different, although there is some overlap in their functions.
Model Expert has lots of functions to help modelers
The EA MDG focuses on implementing all the details of a modeling language