Ask HN: How does Google Analytics, a client-side script, get referring URLs?

[mjswensen]

Shower thought: given that Google Analytics is installed by dropping a JavaScript snippet onto the page, how does Google get the referring page when visitors land on the page via link or search result, etc.?

[Hackbraten]

The script should be able to read `Document.referrer` and post the result to wherever it wants.

[mjswensen]

There it is. Thank you!