An ad placement is a specific group of ad units on which an advertiser can choose to place their ads using placement targeting. Ad placements can be as broad as an entire website or as specific as a single ad unit. Placements are made visible to advertisers in two ways:
- Placements automatically created by our system. Each publisher website in the AdSense network is automatically made available to advertisers as a placement where they can target their ads. When advertisers target this type of placement, their ads may appear anywhere on the website.
- Placements defined by publishers. You have the ability to define your own ad placements using your custom channels. You choose how to group together specific ad units on your site that you want advertisers to be able to target. Common ways of grouping ad units into custom channels are by topic, ad format, or location on a page. When advertisers target publisher-defined ad placements, their ads may only appear in the specific ad units the publisher has selected.