What Google Analytics tracks (and doesn't)
GA4 records anonymous patterns of behaviour on your site: page views, click paths, traffic sources, device types, rough location, and any 'events' you decide are valuable (purchases, sign-ups, downloads). It does NOT record names, email addresses, credit-card data, or any personally identifying information unless you specifically wire it up to send those — which is against Google's terms of service for the standard version.
Translation: GA4 tells you 'a customer in Texas, on iPhone, found you via Google search and bought a $42 product.' It does not tell you that customer was Sarah Williams.
The four sections of GA4 you'll actually use
Ignore the rest until you're ready. These four cover 95% of small-business needs:
- Reports → Realtime — who's on your site right now. Good for verifying your tracking works.
- Reports → Acquisition → Traffic acquisition — where your traffic comes from. The single most important screen in GA4.
- Reports → Engagement → Pages and screens — your best- and worst-performing pages.
- Reports → Monetization → Ecommerce purchases (if you run a store) — purchases, revenue, refunds.
Translating common GA4 phrases
- 'Sessions' = visits. One person visiting twice in a week = 2 sessions.
- 'Users' = unique visitors. Same person visiting twice = 1 user.
- 'Engagement rate' = the share of sessions that lasted >10 seconds OR had a conversion OR viewed 2+ pages. Higher is better.
- 'Conversion' = an action you flagged as valuable. You define what counts.
- 'Channel' = where the visit came from — Organic Search, Direct, Paid, Referral, Social, Email.
- 'Bounce rate' = the inverse of engagement rate. In GA4 a 'bounce' = a session that didn't engage. Lower is better.
What changed when GA4 replaced Universal Analytics
The biggest change: GA4 is event-based, not session-based. In old Universal Analytics, everything was bucketed into sessions. In GA4, every interaction (a page view, a button click, a scroll) is its own event, and sessions are calculated from those events.
Practically, this means your old GA numbers won't match your new GA4 numbers — and that's expected, not a bug. The new metric to anchor on is engaged sessions, which most closely matches what old GA called a 'session with engagement'.
Skip the dashboards — get a weekly summary
Most owners check GA4 once, get overwhelmed, and never go back. Plainly fixes that by emailing you a short, plain-English summary every Monday morning: 'Last week traffic was up 12% — most of it came from a viral LinkedIn post on Tuesday. Your /pricing page converted 3.4× better than your homepage.' That's it. No charts to decode.