http://www.cellml.org/
The purpose of CellML is to store and exchange computer-based biological models. CellML allows scientists to share models even if they are using different model-building software. It also enables them to reuse components from one model in another, thus accelerating model building. CellML includes information about model structure (how the parts of a model are organizationally related to one another), mathematics (equations describing the underlying biological processes) and metadata (additional information about the model that allows scientists to search for specific models or model components in a database or other repository). CellML includes mathematics and metadata by leveraging existing languages, including MathML and RDF. In the future, CellML may also use other existing languages to specify data and define simulation and rendering information. The CellML project is closely affiliated with two other XML-based language projects currently underway at the University of Auckland. Combined, these languages will provide a complete vocabulary for describing biological information at a range of resolutions from the subcellular to organism level.