CMDB Computer - Difference between the fields 'OS Domain' and 'DNS Domain'?

[Tony60]

On the Computer Table (cmdb_ci_computer) ServiceNow created an extra field "OS Domain". On the CMDB-Base table (cmdb_ci) there is already the field "DNS Domain".

Is there a reason why the field "OS Domain" was explicitly created on the Computer Table?

[Dubz]

The OS domain is a computer specific domain that includes user groups and other various bits of operating system topology. The DNS domain is going to be a subnet of domain name which relates to IP networking.

Google is probably a better resource for further details on OS domains and DNS