Arrhythmias can be categorized according to the rapidity of the heart rate at the time of occurrence, the mechanism of occurrence, and the site of occurrence. These include slow and fast types, abnormal impulse formation and abnormal impulse conduction. Arrhythmias can be categorized according to the speed of the heart rate at the time of occurrence as bradyarrhythmias and tachyarrhythmias, respectively. Arrhythmias are categorized as supraventricular arrhythmias and ventricular arrhythmias according to the site of occurrence. Two types of arrhythmias can be categorized according to the mechanism of occurrence: abnormal impulse formation and abnormal impulse conduction. Clinical classification is often based on the speed of the heart rhythm, of which slow arrhythmias include sinus bradycardia, sinus block, sinus arrest, sick sinus node syndrome. Fast arrhythmias include premature beats, ventricular tachycardia, atrial tachycardia, supraventricular tachycardia, and sinus tachycardia. It is advisable to get checked for the type of arrhythmia, which has to be treated according to the specific condition.