Industry WIKI

Audience measurement calculates how many people are in an audience, usually in relation to radio listenership and television viewership, but also in relation to newspaper and magazine readership and, increasingly, web traffic. The term is sometimes used with regard to practices that help broadcasters and advertisers determine who is listening, rather than how many people are listening. I

A target rating point (abbreviated as TRP; also television rating point for televisions) is a metric used in marketing and advertising to compare target audience impressions of a campaign or advertisement through a communication medium relative to the target audience population size. In the particular case of television, a device is attached to the TV set in a few thousand viewers' house