What are supplemental results ?
 

Today I heard about supplemental results. what is this can you pls tell me friends.
I shall be thankful for this reply,so reply must.

From my point of view, supplemental Result is a list of less important URLs indexed in Google's database.

Supplemental results usually only show up in the search index after the normal results. They are a way for Google to extend their search database while also preventing questionable pages from getting massive exposure.

Not getting clear with these posts, I would also like to know about it.

supplemental result is a URL residing in Google's supplemental index, a secondary database containing pages of less importance, as measured primarily by Google's PageRank algorithm.
The importance of a page is measured by the number and quality of links pointing at it.
A supplemental page will still rank in search results, but only if there are not enough pages in the main index that are returned within the search.