Atrial fibrillation arises when abnormal electrical signals suddenly initiate within the atria, taking precedence over the heart's natural pacemaker, which can no longer regulate the heart's rhyth. This leads to irregular and often excessively fast contractions of the atrial heart muscle cells, resulting in a variety of symptoms like an irregular heart rate, palpitations, dizziness, shortness of breath, and fatigue. This M.D. thesis will present a general review on each of the important aspects of atrial fibrillation such as epidemiology, risk factors, etiology, pathophysiology, symptoms, diagnosis and treatment. Treatment will be focusing on rhythm control, rate control, anticoagulation and interventional treatment.