This feature shows sites that link to yours. The feature may be enabled or disabled and the maximum number of referrers designated. This list tends to get large quite fast, so you might want to delete them often. You can also deactivate this feature in the site Preferences or you can setup a maximum number of referrers in the site Preferences.
The frequency of visits, URL of the referring site and the percentage of referring visits they constitute are shown.
Admin options are:
Activate HTTP referrers? Yes No
How many referrers as a maximum?
Note that entries under bookmarks constitute any direct entry of your site URL in a browser bar.