Gmail ads, formerly known as Gmail Sponsored Promotions, allow advertisers to display ads directly in a user's Gmail inbox. The ads appear above the email list in the "Promotions" tab as a collapsed ad that can be expanded. Advertisers only pay for clicks on the collapsed ad. Gmail ads provide accurate targeting based on user information and allow for interactive expanded ads with forms, videos, or links. Advertisers can track metrics like saves, forwards, and clicks to their website from Gmail ads. To set up a Gmail ad campaign, advertisers create a Display Network campaign and add "mail.google.com" as a placement while using templates designed specifically for Gmail ads.