Supports modular modelling

Simile's submodel concept provides a flexible but powerful approach to modularity — building a model up from a number of modules or components. At one extreme, Simile supports plug-and-play modularity: you can simply load a submodel, select an interface file, and all the links between the submodel and the main model are automatically made. This enables a community of researchers to agree on an interface standard, then engineer submodels to that standard. At the other extreme, you can simply load a submodel, then edit it and use influence arrows to link between variables in the submodel and those in the main model. This enables you to make use of other people's (sub)models, even if they were not originally intended for use in your model.

Simile also supports “unplug-and-play”: the ability to extract a submodel from a model and run it as a stand-alone model. All inputs that previously came from the main model now appear as user-specified input values. This is extremely useful for checking out the components of a complex model.