What it means
Five tags appended to a link — source, medium, campaign, term, content — that tell GA4 and your CRM where a click came from. ?utm_source=meta&utm_medium=paid_social&utm_campaign=ramadan_2026.
Why it matters
Without disciplined UTMs, traffic piles up under "direct" and "unassigned" and attribution falls apart. The whole game is a naming convention everyone follows: lowercase, no spaces, a shared spreadsheet or a builder tool. Boring, and the difference between a dashboard you trust and one you argue about.