  In this document and the accompanying documents we describe a data model
(Simulation Data Model) describing numerical computer simulations of
astrophysical systems. The primary goal of this standard is to support
discovery of simulations by describing those aspects of them that scientists
might wish to query on, i.e. it is a model for meta-data describing
simulations. This document does not propose a protocol for using this model.
IVOA protocols are being developed and are supposed to use the model, either in
its original form or in a form derived from the model proposed here, but more
suited to the particular protocol.
  The SimDM has been developed in the IVOA Theory Interest Group with
assistance of representatives of relevant working groups, in particular DM and
Semantics.
