What are the categories of events described in the ITIL service operation book?

Informational and normal overlap conceptually and 'scheduled' is not a recognized ITIL event category - it describes change types, not events.

Scheduled, unscheduled, and emergency are categories used in ITIL Change Management, not event categorization in Service Operation.

ITIL Service Operation explicitly classifies events into three types: Informational events (normal operation, no action required), Warning events (a threshold is being approached, attention needed), and Exception events (something has failed or breached a threshold requiring immediate action). These categories guide how operations staff prioritize and respond to each event.

Reactive and proactive describe approaches to problem management, and 'warning' is only one of the three correct event categories, making this combination incorrect.