Hits: Hits are the individual requests a server answers in order to render a single web page completely. The page document itself plus the various images on the page and any other media files embedded there all represent individual requests to the web server. A hit is a request to the server for a file not a page. In other words, the more images used in a page, the higher the hit count - so while hits may be a good indication of poor page design, they won't tell you much about traffic. Hits are often knowingly quoted by website owners in order to impress potential customers, most of whom are likely to think hits equals visitors - wrong!

Consider this illustration of how misleading 'hits' are. A web page has 10 images (graphics) on it. One individual request to view that page would count as 11 hits - one hit for the HTML code that makes up the page and 1 hit for each of the 10 images 'called' from the server. Hits can be useful for monitoring the on-going performance of a single site, but are virtually useless for comparing the performance of different sites.

Page Views or Impressions: Similar to hits, page views are files requested from the server but are limited to the web pages themselves (i.e., HTM or HTML files). Page views are more useful than hits for comparing the performance of different sites and are also a good indication of how well your site is received.

Unique Visitors: Many people believe that a count of 'unique visitors' is the best way of determining the effectiveness of a web site. Unique visitors are tracked not according to the files they have requested but by their unique IP (or Internet Protocol) addresses, which are much like online fingerprints.