Hosts are the object that the anomaly resides in. They usually reside in programs and aplications. They will often manifest as entities which can manipulate the application.
There are classifications for the hosts based on if they are contained.
The containment scale goes like this:
Contanment Level:[Contained]
Completely seperated from the world.
Containment Level:[Partially Contained]
One or more copies of the anomaly is not contained
Containment Level:[Uncontained]
Can fully access the world