Microsoft's long-promised upgrade to its Windows operating system, Vista, offers a new look, more user-friendly features and new security fortifications that protect the operating system and reduce Internet browsing risks. Vista is available in five versions, from the stripped-down Home Basic version, which sells for about $100, to Vista Ultimate, which sells for $400.

The new look includes menus and windows that cast subtle shadows. Among the new features is a powerful Instant Search tool, which can find files, folders and e-mail messages that contain the search phrase.

To help you determine whether an older computer is compatible with Vista, Microsoft offers an Upgrade Advisor available at www.microsoft.com/windowsvista/getready. Additional computer memory and other upgrades may be required. In some cases, it may be cheaper to buy a new computer with Vista installed than to upgrade.

For more information, visit www.microsoft.com/windowsvista\