Google AdWords: What are Gmail Ads?
#Gmail Ads works a little differently than regular Display Network targeting. An important point of difference is that the ads target users, and not the current email being read.
Gmail Ads (formerly referred to as Gmail Sponsored Promotions) are an innovative way to reach the 900+ million active Gmail users globally. Email is a big part of people’s daily routine, both professionally and personally, which is why Google has been testing ways to bring Gmail ads to advertisers for many years.
All advertisers can now access and implement these ads from their AdWords dashboards.