The Control class is the base class for many of the controls you add to an application. The Control class defines very little behavior; while it is possible to add a Control to your application, it is far more common to add a control that inherits from Control, such as a Button or ListBox.

The Template property, which is a ControlTemplate, specifies the appearance of the Control. Many of the controls that ship with Silverlight use a ControlTemplate and inherit from Control. If you want to change the appearance of a control but retain its functionality, you should consider creating a new ControlTemplate instead of creating a new class. For more information, see Customizing the Appearance of an Existing Control by Using a ControlTemplate.

Control has a derived class UserControl that is the intended base class quickly creating controls. Although the UserControl inherits the template property from the Control class, you cannot apply a ControlTemplate to a UserControl. To create a control that uses a ControlTemplate, see Creating a New Control by Creating a ControlTemplate.

If you want to create a control with custom behavior as well as allow others to customize its appearance, your control can inherit from the Control class and define a ControlTemplate. If you want to extend the behavior of an existing control, you can inherit from a class that inherits from Control.

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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