<unk> is a stage of postgraduate medical training certification in a primary care or referral specialty. In the US it is filled by a resident physician who has received a medical degree (MD, MBBS, MBChB, or DO) and is composed almost entirely of the care of hospitalized or clinic patients, mostly with direct supervision by more senior physicians.  A<unk> may follow the internship year or include the internship year as the first year of<unk>   The<unk> can also be followed by a fellowship, during which the physician is trained in a sub-specialty.
Whereas medical school gives doctors a broad range of medical knowledge, basic clinical skills, and limited experience practicing medicine, medical<unk> gives in-depth training within a specific branch of medicine. A doctor may choose a<unk> in anesthesiology, dermatology, emergency medicine, family medicine, internal medicine, neurology, obstetrics and gynecology, pathology, pediatric medicine, psychiatry, physical medicine and rehabilitation, radiology, radiation oncology, general surgery, or other specialties. The field of surgery has several specialties such as neurosurgery, orthopaedics, otolaryngology, ophthalmology, and urology.
In the United States it leads to eligibility for board certification.
In Canada it leads to eligibility for Fellowship of the Royal College of Physcians or Surgeons of Canada.
In Australia and New Zealand it leads to eligibility for Fellowship of the Royal Australasian College of Physcians or Surgeons.
Residency 
Presentation 
Diagnosis
Measure 
Treatment Planning
Chain of survival
Diagnostic Criteria
Cognitive science