yes, back in the old days, all you needed to "set up shop" was a year of internship, something similar to a "transitional" year of the present. these were general practitioners. now, most people use GP to describe internists (internal medicine physicians). family practice is a separate training/residency program from internal medicine; both are 3 years, i think, but in family you're confined pretty much to outpatient care and preventive medicine that encompasses health care for adults, children, and women's health issues. Internists treat adults, including the inpatient. There's now a movement to create more "hospitalist" residencies for internists who want to focus solely on inpatient care. There are also med/peds and ER/med combined residencies.
At my school, which is allopathic, about 50% go into "primary care" (FP, IM, peds, ob/gyn) and the other 50% go into specialties (surgery, ortho, radiology, anesthesiology, etc.). some people don't count ob/gyn or psych as primary care fields; others do. however, a good chunk of people going into IM here subspecialize (cardio, GI, endocrine, hem/onc, ID, rheumatology, geriatrics, pulmonology, allergy/immunology, etc.).
-s.