The Panel (ASPxPanel) control is a container for other controls and HTML content. Panels allow you to organize web page layout and manipulate the visibility of multiple controls at once.
This demo illustrates how you can use Panel controls to dock page content to any side of the browser’s screen. To dock a panel to a screen side, set the FixedPosition property value to any of the PanelFixedPosition enumeration values. In fixed position, the panel has precedence over master pages.
Panels docked to the top and the bottom of a browser screen overlap the panels docked to the left and the right sides of the window. You can change this behavior using the FixedPositionOverlap property.
Note: A web page can only contain one panel docked to any individual screen side.