creating basic module

Hello Sitefinity,

what is the difference in functionality between "Module" and "widget using user control"
 

From my understanding, a widget is a bit more than a user control (except it can benefit from the Telerik libraries), while a Module is a full functionality including, for instance, a form to add items to a list, and a backend to see the items list and add/edit/delete.
Several examples are delivered with the SP1 SDK, and you have some tutorials on the website too (on the "Documentation" section).

F.

What F said ^ 

Widgets are controls in which users can drag and drop content on to page from the toolbox. A simple example would be a widget that displayed some news.

Modules are a set of pages in which consist of tools to achieve the creation of content.  Using the example above, a module that maintained news would have a page to view all the news entries and a page to look at each entry in detail for example.