Decay types of PDG particles


What exactly do different values of decay types associated with TParticlePDG decay channels mean? I would like to use decay decay data from TDatabasePDG in my code would like to fully understand it first. Looking at the database file I see the label “PY6” so I presume these might be related to PYTHIA6 (especially given that inside the source code, decay type is associated with “matrix-element code”), I would like to make sure though.