Want to know what’s inside sp_help stored proc? How about TABLE_PRIVILEGES view?
All the system objects definitions are now stored in the hidden read-only resource database (a.k.a. RDB) physically persisted in mssqlsystemresource.mdf.
You can view the system objects definitions by running the following query:
where name = 'sys_object_name_here'
If you’re interested in learning more about RDB, there is a good article at http://www.extremeexperts.com/sql/yukon/resourcedatabase.aspx.