Permissions and user rights for IIS 7.0 and later..

This is useful information for IIS servers:

Specify an Identity for an Application Pool (IIS 7)
Read more about  Identities in IIS here..

Default permissions and user rights for IIS 7.0 and later 
Read more about default permissions here..

Understanding Built-In User and Group Accounts in IIS 7
Read more about Built-In user and Group Accounts here..