FHIR defines healthcare data as modular resources ... Patient, Observation, Condition, Medication ... exchanged over standard web protocols. It is substantially easier to build against than earlier messaging standards.

Where This Gets Misread

FHIR standardizes structure, not semantics. Two systems can both be FHIR-compliant and encode the same clinical concept differently, and real-world implementations vary enough that "supports FHIR" tells you much less about integration effort than it sounds like it should.