Campaign parameters added to URLs so compatible analytics systems can identify campaign traffic.
A practical example
A newsletter link can identify its source, medium and campaign while an optional content value distinguishes a particular placement.
What to watch for
Use consistent names and avoid personal information. Tags describe a visit’s label, not proof that a campaign caused an incremental sale.
Related reading
Explore Google Analytics (GA) and Return on Ad Spend (ROAS). Try our UTM link builder for a practical next step. See how this fits into Web development.