A canvas panel is the simplest layout panel in Microsoft Expression Blend, and is supported in both Windows Presentation Foundation projects and Microsoft Silverlight 1.0 projects. It supports absolute positioning and does not apply any layout policy to its child elements—it is literally a blank canvas. Use a canvas panel when fixed positioning is paramount. Elements that you place in a canvas panel will not automatically resize when you resize your application as they can with a grid panel.
Add a canvas panel to a document by using the Asset Library or the layout container button in the Toolbox.