Sharepoint Webpart Differences: .dwp and .webpart

I am sure most of us have come across this situation when users try to add webparts to their SharePoint site and have difficulties with that.  Ever wondered how .dwp and .webpart are different to each other?  Well then here is the answer to this question which is a good one to start with to understand.

The .dwp is a SharePoint web part. This would be one like the Content Editor.  And the .webpart is a .NET framework.

The primary differances are that the SharePoint webparts are built with backwards compatibility and more functionality in the web parts communitcation area. If you needed a web part that worked in WSS 2.0 and WSS 3.0, this would be your guy.

The later is one that most likely originated in Visual Studio.

Source:  http://www.shannonbray.com/2008/07/dwp-vs-webpart.html