Key Event

A key event is an event you have marked as valuable, and the term replaced "conversion" in GA4 reporting.

You flag an event as a key event when it represents something that matters to the business, like a purchase or a lead form submit. GA4 then counts it separately, so you can see how often the outcomes you care about actually happen.

You mark generate_lead as a key event. From then on, every time that event fires GA4 tallies it in the key events column, and you can rank channels by how many leads each one drove.

The word changed, the mechanics did not. GA4 renamed reporting "conversions" to "key events," but marking an event still works exactly as it did. If an old dashboard or doc says "conversion" inside Analytics, this is what it means.

Same job, new name. Mark what matters, ignore the rest.