"The smart tag service in Internet Explorer 6 is available on the following operating systems:
Microsoft Windows 98
Microsoft Windows 98 Second Edition (SE)
Microsoft Windows Millennium Edition (Me)
Microsoft Windows 2000
To turn on smart tags for the operating systems in the preceding list, click Internet Options on the Tools menu, click the Advanced tab, and then click to select the Enable smart tags check box.
Smart tags allow you to find additional information about certain words and phrases that appear on a Web page. When you see a word or phrase underlined with a purple dotted line, you can place your mouse pointer over that word or phrase, and then a list of links to more information about the item is displayed. To view additional information, click the link, and then another browser windows opens displaying that information."
From Microsoft.
