A unique user or visitor is defined as the number of distinct individuals that request webpages from a certain place during a certain amount of time. It does not matter how often the user visits the page. All that matters is the number of people requesting webpages. Users have to have at least one interaction to be considered a unique user. The definition of a unique user has changed over the passing of time, but not by much. Unique users are the number of people that visited a webpage during a given amount of time that are not duplicates at all.