Most hosting companies will provide a statistical package. The information displayed varies according to the package but should include:
Number of visitors – how many visitors have been to your site in the past month?
Where the visitors have come from – how did the visitors to your site find you? Was it via the keywords you have optimised the site for or did they use a different set of words?
Number of pages viewed – how many pages did the visitor look at?
All of this information can be used to market your website more efficiently.