An 'event' doesn't need to be temporally connected. For example, several instances of switching on a heater over a week may be represented by a single 'event' individual; it will occupy a non-singular 'instant region'. The details of a singular event part may be modelled by relating the event to 'instant' individuals.
Event is close in meaning to BFO's 'process boundary', and to DOLCE's 'achievement'.
The IDO treatment of 'event' differs from BFO, where 'process boundary' (BFO_0000035) is a sibling class to 'process' rather than a subclass. With IDO, a property chain axiom on 'has participant' implies that activity-bounding events share participants with the activities they bound.
'event' is a subclass of 'activity': an occurrence in which physical objects participate. What distinguishes an event is the restriction that its temporal extent is an instant region rather than an interval. The term 'event' and the subclass placement are inherited from ISO 15926-2.
