Glossary
Popup
A window or layer that opens in front of the page, on load, on a timer or when the visitor tries to leave. Used for offers, discounts, subscriptions and exit intent. Blocked by most browsers when it is a real new window.
Also called: pop-up.
Modern popups are layers inside the page rather than windows, because browsers block the old kind. Exit-intent popups catch a visitor leaving a lander with a last offer; timed popups push a subscription.
As a paid format, popup traffic is mostly popunder traffic under another name; networks use the two words loosely.
Related terms: Popunder, Overlay ad, Push notifications.