A doctor interacts with patients, diagnoses medical problems and treats illness or injury. There are many specific areas in the field of medicine that students can study to become doctors.

Approximately half of all doctors work in a hospital; these doctors diagnose and treat medical conditions, disorders, and diseases through the application of specialist medical skills and knowledge. Hospital doctors can work in a number of specialties, from emergency medicine to surgery. Hospital doctors treat people who have been admitted or referred to hospital. 

There are many, many types of doctor, but some of the most needed by people regularly are; family physicians, paediatricians, psychiatrists obstetricians and gynaecologists surgeons anaesthesiologists, and pathologists.

The length of time a training doctor will go to school depends on the specific area of medicine they’d like to work in, but all doctors must complete a four-year undergraduate program, along with four years in medical school and three to seven years in a residency program to learn the specialty they chose to pursue. In other words, it takes between 10 to 14 years to become a fully licensed doctor. 

A surgical residency adds the most time, and neurosurgery the most. In the United States, neurosurgery residency training takes seven years after medical school. It is longer than any other medical or surgical specialty.