What it means
In client-side tracking the browser sends events straight to Google, Meta, and others. Server-side routes those events through a server you control first. You decide what is shared, enrich it with first-party data, and the data is far less exposed to ad-blockers, Safari''s ITP, and network failures.
Why it matters
Browser-based tracking now loses a large share of events. Server-side tagging plus the platforms'' Conversions APIs recovers much of that signal, which directly improves ad optimisation and reporting accuracy.