An action or event that can be counted–such as a purchase, sign-up, or download. Conversions drive optimal business outcomes for a performance campaign. “View” or “view-through” conversions are counted when a user has viewed an impression but did not click on it, whereas “click” or “click-through” conversions only count a conversion when a user has clicked on the ad shown for that impression. View conversions can be attributed to numerous partners, but click conversions can be tracked only on “last click,” meaning the most recent in time before the conversion event.