# Recorder

In the recorder panel you specify the species and/or reactions that you want to record in the simulation output. Press or to select or deselect all of the species or reactions. If you modify a model the recordable items will be updated automatically. The items that may be recorded depend on the type of simulation. When generating uniformly-spaced time series data you may select any combination of species and reactions. For trajectories that record all reaction events, all of the species and reactions are marked as being recorded. When using histograms to record stochastic trajectories, you may select any combination of species.