- Things (Serious_Student)
- States (It_Is_Raining)
- Processes or time phase(Morning_Routine)
- Activities (Attend_class)
- Instantaneous event or condition (Raindrop_spotted)
- used for most MP keywords (see MP Guide Section 7) – do not use for user defined names
- not recommended
MP names for events do not have to be unique across ROOTs. If an event is intended to be mutual (shared) you might wish to use the same name.