The Component class provides the base class for all ASP.NET AJAX client controls, behaviors, and non-visual components on the page. It also provides the static create method, available as Sys.Component.Create or as the $create shortcut method, as a means to add an instance of a component, control, or behavior to your application. The create method is preferred over Sys.Application.addComponent because it sets all the properties that are required to define a component instance on page.
The Component class implements the INotifyDisposing interface. Any object in your application can subscribe to the disposing event of a component and use the event as a signal to dispose itself or to do other work. The Component class also implements the INotifyPropertyChanged interface, and therefore raises propertyChanged events. These events can be handled internally, subscribed to by other components, or both.
For information about how to create custom components that derive from Component, see the following topics.