Cookies are small text files on your computer, used to keep track of settings or data for a particular Web site. Web sites can use cookies to identify a returning user or to pass information between web pages in a single visit. There are two types of cookies: temporary and permanent. Temporary cookies are used and tracked by the browser to pass information and are deleted once the browser is shut down. Permanent cookies are stored on your system and can be accessed again for multiple visits. Permanent cookies usually have an expiration date and will be automatically deleted from your system at that time. When you choose "Yes, register my private computer" after entering an access code, a secure cookie (a computer data file) will be placed on your computer after you complete the login process. This secure cookie, when used in combination with your login information, creates a unique way for Tower to identify your computer. After you add extra security to a computer, every login attempt, is validated using your standard login information was well as the information contained in the secure cookie. The cookie is only used by Tower to validate your identity and does not contain any personal information.