What are "unique users?"
Top9.com rankings are based on a calculation of the number of unduplicated monthly visitors to a site. An individual "unique user" is counted only once during the survey period for a particular site, no matter how often the individual visits. If a site ranks below 10,000 the unique users number is not shown, since there is a greater margin of error in calculating this figure.

What is "overall Web ranking?"
Every Web site receives an overall ranking among all Web sites. This is the site's relative position to the entire Web listing, regardless of category. For example, say a site has an overall Web ranking of 2,458. This means that of all the millions of Web sites on the Internet, it ranked for the previous month as the 2,458th highest of all the sites.

What does "composite visitors" mean?
"Composite visitors" is simply the sum of all "unique users" for Web sites within a sub-category. Currently, this number is not scientifically compiled; it is used simply for ranking purposes among sub-categories. Eventually this number will be derived scientifically.

What is meant by "URLs in Cat?"
This is simply the total number of URLs we have classified to date for a particular category. Only the top 18 sites are shown in the Top 9 listing each month, although there may be dozens or even hundreds classified in that category.

When are new rankings displayed?
Our goal is to have new monthly rankings appear within ten days after the end of each month. Eventually Top9.com will feature weekly rankings.

What about "(your favorite here)" for a new category?
We have lots of requests to include everyone's favorite category. As Top9.com grows, we will continue to add categories based on their overall popularity. The more popular topics and subjects have more highly ranked sites, and thus are the first to appear.

How are sites ranked?
Many sites are extremely difficult to classify; others fall easily within many categories. We have taken a 'common sense' approach in classification, in which we assess a site based on how the typical consumer would interpret it. Each site appears in only one category. If a site has multiple 'sibling sites,' or if several different URLs lead to the same site, only the highest ranked site is listed.

What are "related sites?"
On each page you will find a listing of "related sites." This is a navigation aid, which lists categories, sub-categories and individual URLs that are closely related to the Top 9 listings on that page.

Why is my site not listed? We get lots of hits...
If your site is not listed under the category you prefer, make sure it is not listed elsewhere. Contact us if you think your site is listed incorrectly. If your site is not listed at all, it is not among the nine highest-ranked sites for that sub-category. Site rankings are provided by PC Data Online. If you feel your site has ranked too low, please visit the PC Data Web site for further explanations and methodologies. Keep in mind that the hit counter on your site will provide a much larger number than will our "unique visitors" ratings. There currently is no provision for analysis of specific Web site traffic.

Other answers and more details on methodology can
be found on the "About Us" page, or on the PC Data Online "Methodology" page.