Rick's page on information elements is definitely one of the best I've read.
But in summary:
External/Internal - A subtle difference really. Kind of hard to pinpoint precisely, but External deals with the more concrete while Internal deals with the more abstract.
Dynamic/Static - Implies a sense of motion. Dynamic is fluid, deals with things as if they are constantly changing and interacting, think of things rolling outwards. Static deals with things in instants or snap shots, rather than rolling outwards it builds in singular pieces.
Object/Field - An objective/subjective dichotomy. Object is more observational while Field is more judgmental (not to mistaken with judging and perceiving). Object classifies information by seeing what is going on, Field classifies information by deciding what is going on.