Example #1: There is an easement on Parcel A that allows the owner of Parcel B to cross Parcel A for purpose of ingress and egress. Parcel B is the dominant estate since it receives the benefits.
Parcel A is the servient estate since it provides the benefits.
Example #2: Georgia Power has an easement on Parcel A. Parcel A is the servient estate because it provides the benefits. There is no dominant estate.