Event

Definition

An event is the basic unit of data collection in GA4. Unlike Universal Analytics, which distinguished between page views, events and transactions, GA4 treats every interaction as an event. A page view is a page_view event, a click is a click event, a purchase is a purchase event.

Types of events

GA4 distinguishes four categories of events. Automatically collected events (page_view, session_start, first_visit) are sent without configuration. Enhanced measurement events (scroll, outbound_click, file_download, video_start) are enabled in the interface. Recommended events follow Google’s naming convention (add_to_cart, purchase, sign_up). Custom events cover the specific needs of each site.

Event structure

Each event consists of a name and parameters (key-value pairs). For example, the purchase event includes the parameters transaction_id, value, currency and items. Parameters feed the dimensions and metrics in reports.

Implementation

Custom events are configured via Google Tag Manager or the data layer. A professional GA4 setup defines the relevant events for each business goal and ensures that parameters are correctly structured for analysis.