Google Analytics 4 Complete Beginner's Guide: Understanding Your Website Data

This is a pure content writing task (SEO copywriting), not involving visual design; brand design system is skipped. The HTML article conforming to GEO rules is

This is a pure content writing task (SEO copywriting), not involving visual design; brand design system is skipped. The HTML article conforming to GEO rules is produced directly as follows: --- On July 1, 2023, Google Analytics 4 officially ceased Universal Analytics data collection, leaving tens of millions of websites worldwide with no choice but to rely on GA4 to understand traffic behavior. However, GA4's data model differs fundamentally from its predecessor — directly applying the interpretive frameworks from the UA era will lead to severely flawed judgments. Understanding the underlying logic of the event-driven architecture is a prerequisite for turning GA4 numbers into genuine business decision-making insights. The Fundamental Differences Between GA4 and Universal Analytics Universal Analytics used the Session as the basic unit of data; GA4 shifted to Events as its core. This fundamental change affects the calculation logic of every metric in the dashboard. In UA, a user viewing 3 pages generates 1 Session and 3 Pageviews; in GA4, the same behavior generates 3 independent page_view events, each carrying its own parameters such as page path, title, and scroll depth. "Universal Analytics ceased processing all hit data on July 1, 2023; GA360 was extended until July 1, 2024 (Source: Google Analytics Official Support Documentation)" , meaning that websites relying on UA historical data have been accumulating an irreversible data gap since that day. Bounce Rate Disappears, Engagement Rate Takes Its Place GA4 fully replaces Bounce Rate with Engagement Rate; the two metrics are calculated completely differently and cannot be used interchangeably. "GA4 defines an engaged session as one that meets any of the following criteria: lasts more than 10 seconds, includes 2 or more page views, or triggers at least 1 conversion event (Source: Google Analytics Help Center)" . Engagement Rate = Engaged Sessions ÷ Total Sessions. For the same website, a GA4-reported "Engagement R