Facebook Audience Insights gives advertisers in-depth demographic, location, and activity data about groups of Facebook (FB -0.9%) users (but not individuals), with the goal of allowing them to fine-tune their ads based on the information they uncover.
The feature complements Custom Audiences, a popular ad targeting solution that leverages data on non-Facebook activity (both offline and online/mobile), and Lookalike Audiences, a solution that lets advertisers target users with traits similar to existing customers. Audience Insights info can be provided for Custom Audiences groups, as well as for people connected to a page/event and Facebook users in general.
Improved ad targeting tools have helped drive the big ad price improvements Facebook has seen in recent quarters. Sheryl Sandberg mentioned on the Q1 CC the number of advertisers using Custom Audiences has grown 10x Y/Y.