So we see that the electrocardiogram is the fluctuations, the change in voltage that is produced by the heart. And this voltage is used to basically generate that muscular contraction that propels all that blood through the blood vessels of our body. Now, in this lecture, we're going to study the normal electrocardiogram. We're not going to discuss any abnormalities that might exist within the heart and that might be described by an abnormal electrocardiogram. So we're simply going to focus on the brief details of a normal electrocardiogram. So let's take a look.