Even though it's not as dominant as it was 8 or 10 years ago, Internet Explorer continues to hold about 60 percent of the browser market. For many people, the little blue "e" is their one and only entry to the Web--they may not even realize the program has a name.
If you use Internet Explorer, the most important thing you can do to improve your safety on the Web is to upgrade to version 8. If you have Windows set to update automatically, you're probably already using the most recent release. To check your IE version, click Help > About Internet Explorer.
by Dennis O'Reilly
The best Internet Explorer security add-ons