specified period, the number of visits may be greater than the number of visitors. A visitor is sometimes referred to as a unique visitor or a unique user to clearly convey the idea that each visitor is only counted once. The purpose of tracking unique visitors is to help marketers understand website user behavior. The measurement of users or visitors requires a standard time period and can be distorted by automatic activity (such as bots) that classify web content. Estimation of visitors, visits, and other traffic statistics are usually filtered to remove this type of activity by eliminating known IP addresses for bots, by requiring registration or cookies, or by using panel data. See also Active users Hit (Internet) Registered user Web traffic Web analytics Further reading Notes Advertising indicators Web analytics Network addressing fr:Audience d'un site Web#Définitions et vocabulaire