Unless it is an 'easement in gross', which is a particular form used for things like council stormwater pipes, every easement must have a dominant and a servient tenement. All easements must be attached to existing titled land. It creates specific rights of use for a determined area of the servient tenement in favour of the dominant tenement. It does not affect ownership in any way.
In a simple form, it is a registered contract that gives someone the right to use part of your land for a stated purpose, in return for which you are paid a fee (which could be $1).