Audience targeting means showing advertising to groups of people defined by interests, behaviour, demographic data, or by signals of purchase intent. The data is estimated by the advertising system from user activity, so the accuracy is limited and some of the classifications tend to be inaccurate. In search campaigns, audiences are best used as a supplement that adjusts the bid for selected groups, not as the sole criterion. In display and video campaigns, by contrast, they are the main tool, since keywords do not apply. Audiences built on the company's own data – website visitors and customer lists – have particular value, as they are more accurate than the platform's estimates. Their use, however, is subject to consent and to personal data protection rules.
See also: Lookalike audiences, Customer lists in advertising, Audience exclusion.
