Spry widgets are replaced with jQuery widgets in Dreamweaver CC and later. While you can still modify existing spry widgets on your page, you cannot add new spry widgets.
The Spry framework is meant primarily for users who are web design professionals or advanced nonprofessional web designers. It is not intended as a full web application framework for enterprise-level web development (though it can be used in conjunction with other enterprise-level pages).
For more information on the Spry framework, see www.adobe.com/go/learn_dw_spryframework.