What is the difference between the Target and the Evaluator subfields in the output from FindExternalEvaluators[]?

In the documentation for the "Python" external evaluation system, an example is given where the Evaluator option is set to an association that sets up a python environment by specifying a name for the environment, a python executable, dependencies, and a base directory.

On the other hand, in the documentation for ExternalEvaluate, the Target option is used in one of the examples for essentially this same purpose.

Note that FindExternalEvaluators[] reports back a both an Evaluator and a Target field for each entry, that in the default configuration are each set to the file path for the python executable.

Since both of these fields also exist for the non-python systems, I would like to understand the intended distinction between them on a more abstract level as well.