Windows 7 introduces a desktop slideshow feature that periodically changes the desktop wallpaper based on a user-defined interval; the change is accompanied by a smooth fade transition with a duration that can be customized via the Windows Registry.The desktop slideshow feature supports local images and images obtained via RSS.Support for themes has been extended in Windows 7. In addition to providing options to customize colors of window chrome and other aspects of the interface including the desktop background, icons, mouse cursors, and sound schemes, the operating system also includes a native desktop slideshow feature. A new theme pack extension has been introduced, .themepack
, which is essentially a collection of cabinet files that consist of theme resources including background images, color preferences, desktop icons, mouse cursors, and sound schemes.The new theme extension simplifies sharing of themes and can also display desktop wallpapers via RSS feeds provided by the Windows RSS Platform. Microsoft provides additional themes for free through its website.