Diff between Portlet Embed and Portlet Include

I’m using MWS 7.1.3.
I need to show a portlet in a modal dialog of a different portlet.
When i see the palette there are 2 controls which does the above. Portlet Embed and Portlet Include.

May i know what is the main difference between the both and suggest me which control to use in the above case.

Portlet Include will just reference a pre-existing instance of a portlet, but portlet embed will create a new instance of the portlet for this application. It will create the embedded portlet as a child of the portlet that you are currently interacting with (if it doesn’t already exist).

Hope this helps.