Event

An event is any tracked user interaction and the core unit of data in GA4.

Everything GA4 records is an event: a page view, a click, a scroll, a purchase. Each one carries a name and a set of parameters that describe it, and every report you read is built by counting and slicing those events.

When someone loads a page, GA4 fires a page_view event. When they play an embedded video, it fires a video_start event. Same data type, different name and different parameters.

Not every event is worth acting on. GA4 collects far more events than you will ever report on, and raw event count tells you nothing until you decide which events map to actual outcomes.

In GA4, if it happened, it is an event.