| AbstractLoader | In a nutshell, loaders pack (create) cargos (variable holders) and load them to particles (nodes). |
| FieldsLoader | Helps set up the fields of a particle (aka node) |
| IncomingEdgeLoader | Helps set up the incoming edges of a particle (aka node) |
| OutgoingEdgeLoader | Helps set up the incoming edges of a particle (aka node) |