Now, let's take a look at the following diagram briefly. So our y axis is the velocity, which is basically another way of saying the rate or activity of that enzyme. Now the x axis represents the concentration of substrate. So notice as we go to the right, along the x axis, we increase the concentration. And as we go up along the y axis, we increase the velocity or the rate of activity of that enzyme. Now, this slope, shown in purple basically describes the relationship between the concentration of substrate as well as the velocity or rate of activity of our enzyme.