ECG or electrocardiogram measures the heart activity and in case of any abnormality the peaks on ECG fluctuate that gives insight into heart anomalies. Heart muscles are myogenic because they are capable of generating their own impulse without the involvement of the brain. ECG has 3 major peaks P QRS T P signifies contraction of both atria that is caused by generation of signal in S-A node. After that impulse travels to ventricles after it has passed A.V node and his-purkinje fibers causing depolarization of ventricles leading to formation of QRS peak. As the ventricles repolarises T wave is formed.