There are three types of Web site statistics, a hit, a page view or pages and a visitor or visits. Each of these measures something different:
Hits – A single file request in the access log of a Web server. For example, a request for an HTML page with three graphic images will result in four hits in the log: one for the HTML text file and one for each of the graphic image files. While a hit is a meaningful measure of how much traffic a server handles, it can be a misleading indicator of how many pages are being viewed. Instead, advertising agencies and their clients look at the number of pages delivered and ad impressions or views.
Page Views / Pages – This measures how many times someone has viewed an entire page including all text, images, etc.
Visitors / Visits – This is defined as a series of hits from any particular IP address. If any two hits are separated by 30 minutes or more, two visitors are counted. “Visitors” represent an extrapolated number.