Within AJAX control Toolkit most of the controls are extender controls. Extender controls are the controls that extend the functionality of existing controls of Asp.net & these controls are not separate independent controls. The extender controls available in AJAX Toolkit are as follows.
Ajax Filtered Text Box Extender
Ajax Dynamic Populate Extender
Ajax Mutually Exclusive Check Box Extender
Ajax Paging Bulleted List Extender
Ajax Resizable Control Extender
Ajax Text Box Water Mark Extender
Ajax Validator Callout Extender