That means, you cannot install the SharePoint on the Domain Controller or on a workgroup PC (which is not part of Domain). This type of deployment is not supported by MSFT, that means you will not get support from MSFT in cases of issue.
There are many known issues when you install SharePoint on Domain Controller
- User Profile & MySites will not work
- You will see unseen issue with Search
- One of the error:
ErrorCode:SubStatus: Service running under Network Service account in workgroup environment is not supported
- Security Issue.
- Service Packs, Infrastructure updates, hot fixes and the like all
require the SharePoint Technologies wizard to be re-run on every
server in the farm. The wizard assumes that the local WSS_* groups
already exist and that certain permissions are already in place.
Being on a Domain Controller can have unexpected results.
- Reporting Services and other wizards run expecting local services
which do not exist on a DC.
- You will not be able to use Document Conversion at all. There is no
work around or a resolution to this.
But one thing, it is supported by the Developer's machine (only on Domain Controller).
https://briankgough.wordpress.com/2009/07/16/sharepoint-on-a-domain-controller/