What is primary, secondary, stub & ad integrated zone?

Primary Zone:- DNS server hosts is a primary zone and it stores the master copy of zone data in a local file or in AD DS.

Secondary Zone:- secondary zone is merely a copy of a primary zone that is hosted on another server, it cannot be stored in AD DS.

Stub Zone:-  This DNS server must have network access to the remote DNS server to copy the authoritative name server information about the zone.

AD Integrated Zone:- When you store a primary zone in AD DS, the zone type is changed from primary to Active Directory (AD)-integrated.