well I know definations of these terms as mentioned:
Ghosted pages: Pages which are on file system and not on content db.
Unghosted pages : pages which are on content db.
Application Pages : normal asp.Net pages stored on file system.
site pages : Normal content pages stored in db.
According to these definations Site pages should always be Unghosted and Application pages should always be Ghosted.
Now here comes the problem: SP virtual path provider: provides virtual path for both ghosted and unghosted site pages. How site pages be ghosted? This msdn link(http://blogs.msdn.com/b/steve_fox/archive/2010/03/08/ghosting-unghosting-in-sharepoint-2010.aspx) also talk about ghosting and unghosting of site pages.
Could some one please explain to me these things.