Google Analytics 4 (GA4)

GA4 replaced Universal Analytics in 2023 with a unified event-based data model that spans websites and apps. Every interaction (pageview, scroll, click, conversion) is captured as an event with parameters, enabling more flexible analysis than the old session-and-pageview model.

Properly configured, GA4 powers attribution, audience building, and conversion tracking. Misconfigured, it produces misleading numbers, which is why instrumentation, server-side tagging, and consent management are now first-class concerns rather than afterthoughts.