Example simulations. A. SBML model of calcium oscillations in astrocytes simulated in STEPS with the deterministic solver Wmrk4 (results plotted at 4 second intervals) shows perfect agreement with BioModels Online simulation. B. SBML model in a femtoliter compartment is simulated in STEPS with the stochastic solver Wmdirect (results plotted at 0.8 second intervals) and compared to BioModels Online deterministic simulation. Shown are cAMP and Ca signals, which are controlled by Events. Small stochastic differences are noticeable between simulations.