User Interface

Windows XP featured a new task-based GUI (Graphical user interface). The Start menu and Taskbar were updated and many visual effects were added, including:

• A translucent blue selection rectangle in Windows Explorer
• Drop shadows for icon labels on the desktop
• Task-based sidebars in Explorer windows ("common tasks")
• The ability to group the taskbar buttons of the windows of one application into one button
• The ability to lock the taskbar and other toolbars to prevent accidental changes
• The highlighting of recently added programs on the Start menu
• Shadows under menus (Windows 2000 had shadows under mouse pointers, but not menus)

Windows XP themes

Default Blue (Luna)	Windows Classic
XP Media Center	The new start menu design in the "Energy blue" theme.
The "task grouping" feature introduced in Windows XP showing both grouped and ungrouped tasks.

Windows XP analyzes the performance impact of visual effects and uses this to determine whether to enable them, so as to prevent the new functionality from consuming excessive additional processing overhead. Users can further customize these settings. Some effects, such as alpha compositing(transparency and fading), are handled entirely by many newer video cards. However, if the video card is not capable of hardware alpha blending, performance can be substantially degraded, and Microsoft recommends the feature should be turned off manually. Windows XP added the ability for Windows to use "Visual Styles" to change the appearance of the user interface. However, visual styles must be cryptographically signed by Microsoft to run. Luna is the name of the new visual style that ships with Windows XP, and is enabled by default for machines with more than 64 MiB of RAM. Lunarefers only to one particular visual style, not to all of the new user interface features of Windows XP as a whole. Some users "patch" the uxtheme.dllfile that restricts the ability to use visual styles, created by the general public or the user, on Windows XP.

In addition to the included Windows XP themes, there is one previously unreleased theme with a dark blue taskbar and window bars similar to Windows Vista titled "Royale Noir" available as unofficial download. Microsoft officially released a modified version of this theme as the "Zune" theme, to celebrate the launch of its Zune portable media player in November 2006. The differences are only visual with a new glassy look along with a black taskbar instead of dark blue and an orange start button instead of green. Additionally, the Media Center "Energy Blue" theme, which was included in the Media Center editions, is also available to download for use on all Windows XP editions.

The default wallpaper, Bliss, is a BMP photograph of a landscape in the Napa Valley outside Napa, California, with rolling green hills and a blue sky with stratocumulus and cirrus clouds.

The "classic" interface from Windows 9x and 2000 can be used instead if preferred. Several third party utilities exist that provide hundreds of different visual styles.