Website visits / GRP, also known as Gross Rating Point, is a metric used to measure the effectiveness of online advertising campaigns. It is calculated by dividing the total number of visits to a website by the total number of impressions (or views) of the ad. This metric provides valuable insights into the reach and frequency of an ad, allowing advertisers to gauge the impact of their online presence. A higher Website visits / GRP indicates a higher level of engagement and interest from the target audience, making it a crucial tool for measuring the success of digital marketing efforts.