Advertisers or buyers typically want to reach an intended audience or demographic with their campaigns. Targeting helps you build expressions that determine how and where ads serve to reflect the goals of your advertisers or buyers. Targeting can be broad or granular.
Typically, targeting is applied to line items or proposal line items. However, targeting is applicable to many parts of Ad Manager—Protections and unified pricing rules, for instance, features that help you manage inventory in the Open Auction. Wherever you use targeting, concepts and behavior are the same across Ad Manager.
Targeting restrictions
You may not pass any personally identifiable information (PII), including names, addresses, or user IDs, in targeting. Mask this information using the encoding method of your choice, and ensure traffickers know how to decode values when setting up a line item.
Google Ad Manager doesn't read your site's cookies and doesn't have connections to your web systems. JavaScript tagging is the only way to pass information to Ad Manager. You must pass information to Ad Manager on every page because the information isn't stored with the user.
Google Ad Manager doesn't share information with other publishers, so there is no built-in pool of demographic data to target.
Learn how to add targeting in: