User Agent String
Some companies track Web site statistics, such as how many times their content is accessed and what type of Web browsers are being used. You can track the use of your customized version of Internet Explorer by using a user agent string, which is sent in the header of every HTTP request so that a site's Web server can detect what type of browser is being used.
In this page in the Internet Explorer 7 Customization Wizard, you can customize the user agent string by adding characters to the end of the string. Customizing the user agent string is optional, but if you decide to do this, be aware that other companies that track site statistics will see the customized string.
For Internet Explorer 7, the value MSIE 7.0 (with a space) is used to identify browser type.
The recommended maximum size for the user agent string is 200 characters.
Customize string to be appended to user agent string
Select this check box to customize the user agent string.
Custom string to be appended to user agent string
The string you type in this box is appended to the user agent string for the customized browser. You do not need to customize the user agent string unless you want to track the usage of your custom browser.