They can easily get information such as IP address (and your city and ISP from that), browser (including version), operating system, whether Javascript, Flash, etc. are installed/enabled, the referring website, how many (and perhaps which) websites you've viewed in that window, your monitor resolution, etc. Only your IP address is passed along when you send an e-mail, but websites can check such information when you visit.
John
Hi,
Is information such as the "computer name" sent to e-mail sites (ex. yahoo, gmail etc.) besides things like ip addresses? What other types of information is also sent when logging on to those services? I appreciate your help. Thanks!

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