Doctor is an academic degree, awarded by a university or similar institution. "Doctor" may be used to refer to a person with a doctorate.
To get the degree, people need to pass a doctorate exam, or write a thesis or dissertation. The requirements vary according to the subject-matter.
There are three levels of university qualification:
The first level of these, the Bachelo's degree, covers the basics; the things that people will need in their job almost every day. There is very little specialization. A bacheolor's degree usually takes 3-4 years.
The second level covers specializations; usually people need a bacheolor's degree in the same branch, or a closely related one. The master's degree is about more advanced cases, and specializations. It usually takes another 1.5 to 2 years.
So, people can do a master's degree in about 4.5-5 years. People who do a doctorate write a theseis that can answer one, or a few very specific questions. With the doctorate, they show that they are capable of doing research. Usually, a doctorate takes andother 3-5 years after a master's degree.
Depending on the country, there are cases where people get what is called a professional doctorate. This is mostly the case in law, and in medicine. A professional doctorate is comparable to a master's degree.
People who have a doctor's degree may use the title "doctor", though in practice it is often used only by medical doctors. Medical doctors examine, diagnose and treat patients. They can specialize in a number of medical areas, such as pediatrics, anesthesiology or cardiology, or they can work as general practice physicians. Becoming a medical doctor requires a doctoral degree in medicine and participating in clinical training. Medical doctors need a licence, and certification may also be required for many specialists.