While family doctors cover a wider range of diseases and symptoms, there are doctors that specialize in certain fields of disease, prevention and injury. The specialties branch out even in the emergency room field of medicine.

A D.O. is a fully licensed doctor, with the added benefits of hands-on diagnostic ability and a holistic philosophy. The medical treatment of a D.O. has a complete background and understanding of how all of the body systems function as one. D.O. stands for doctor of osteopathic medicine.

Doctors with an M.D. set of initials following their name is a doctor of allopathic medicine, which in layman's terms means they use medications for the treatment of disease or illness. An M.D. treats and diagnoses injury, illness and disease with the use of all the treatments available through modern medicine and can prescribe medications to assist in healing.

A doctor of podiatric medicine, or P.D.M., is a doctor that is licensed to diagnose, prevent and treat disease, injury and prevents problems with the ankles and feet. These doctors study for four years and take on a residency for 36 months before being tested in their specialized medical field.

If you've ever had a surgical procedure done, you've met an anesthesiologist. Anesthesiologists pass medication either intravenously or through a mask to place a patient in a state of calm or sleep during the surgery. The anesthesiologist's main function is to remain during the surgery to monitor the patient's vital signs and condition throughout surgery and to provide any pain management for acute and chronic conditions.

Cardiologists, Interventional Cardiologists and Cardiac Electrophysiologist all have training for the specialized field of the heart and circulatory system. A cardiologist specializes in diseases of the heart and blood vessels, while an interventional cardiologist works with imagery to locate, diagnose and treat diseases in the heart and vessels. Cardiac eletro physiologists specialize in working with electrical problems of the heart, such as an irregular heartbeat is caused by an electrical problem in that area.

Cardiovascular Surgeons and Cardiothoracic Surgeons specialize in the chest or in areas surrounding the heart and circulatory system, and can treat diseases and problems via surgical procedure. A cardiovascular surgeon works in the management of the circulatory system and heart disorders, while the cardiothoracic surgeon treats in pathological conditions within the chest itself. A pathological condition refers to disease.

Endocrinologist can diagnose and treat hormone imbalances, thyroid disease, diagnose and treat diabetes and other disorders of the endocrine system.

A family medicine doctor, or family practice physician provides us with a general, well-rounded, versatile body care specialty. These doctors can care for all ages, both sexes, has knowledge of each organ system and every disease. Disease and prevention of disease is the main goal of a family physician.

Gastroenterologists study and treat the disease and malfunctions involving the digestive system.

A Geriatrician is a general practice doctor who specializes in the treatment, diagnosis and care of the elderly.

A hematologist treats diseases of the blood and marrow.

Diseases of the liver are diagnosed, treated and cared for by a doctor referred to as a Hepatologist.

The doctors you may visit in the emergency room or in a hospital room in general is called a Hospitalist. These are internal medicine physicians whose practice is limited to the care of hospitalized patients.

Hospital-based critical care or intensive care patients receive their care through an Intensivist.

An internal medicine doctor provides us with diagnosis, care and management through non-surgical treatment surrounding types of unusual or serious disease.

A medical geneticist can assist with the treatment, diagnosis and therapy of genetic disease.

An oncologist locates, diagnoses and treats all types of cancers and tumors, while a radiation oncologist applies radiation therapy to manage these illnesses.

Neonatologists' studies and cares for premature and critically ill newborn babies.

Nephrologists studies and treats all diseases of the kidneys.

Neurology is a specialized field that involves all types of disease and functions of the brain, spine, peripheral nerves, muscles and nervous systems. A neurologist is the medical doctor that treats and diagnoses problems involving the neurological system. A neurosurgeon provides surgical abilities when needed for the nervous system.

A neurophysiologist is a doctor that has done specialized study in the field of the nervous system, but can administer electrophysiologic testing to diagnose the disorders of the peripheral and autonomic nervous systems.

For the female reproductive system, specialists in this field are the obstetrician, the gynecologist and the urogynecologist. An obstetrician or gynecologist studies and cares for the medical and surgical aspects of the female reproductive system while the urogynecologist specialize in female urological problems.

An Ophthalmologist deals in the field of eye and vision care, including the ability to medically or surgically treat disorders. An optometrist diagnoses diseases of the eye and has the specialized training to correct vision problems.

Orthopedic surgeons, or orthopod as they are sometimes known as, is a medically trained specialist relating to the field of disorders of the musculoskeletal system. These doctors can diagnose and treat injuries or disease in this area.

Otolaryngologists are physicians specializing in throat, ear and nose problems.

A pathologist is a trained doctor who usually works behind the scenes to diagnose the diseases concerning the tissues, body fluids and organs. Pathologists are called in to work on crimes committed, due to the ability to process data concerning these areas of the human body.

A perinatologist specializes in the care of women that are pregnant, but have high-risk pregnancy issues.

A physiatrist is a doctor that specializes in physical medicine and rehabilitation of the patient.

Podiatrists are specialized in the medical and surgical deformities of the foot and ankle.

Pulminologists are doctors who specialize in the lung area of the body.

A radiologist is a trained specialist who can perform and interpret imaging test such as x-rays or MRI's. An interventional radiologist can perform minimal procedures like the ability to perform embolizations, thrombolysis and biopsies, using imaging guidance such as the use of the ultrasound machine, which can be used to find tumors, blood clots, etc. A thrombolysis is the breaking up of a fibrous clot that can be located in a chamber in the heart, or in an artery.

Rheumatologists would be a physician you are referred to if you have arthritis or a disease of the joints, as well as the autoimmune disorders like lupus, a disease where the immune system attacks your own tissue and organs.

Sleep doctors diagnose and treat sleep disorders and can help someone obtain knowledge as to why they are not sleeping to help them prevent further sleep loss.