The scale tells us what 1 unit of the x-axis and y-axis represents. Hence, it is very important to decide on a suitable scale before plotting the points.    For example, say you have data values of 2, 4, 6, 8, 10… and each division on the x-axis is marked as 3, 6, 9… here the scale is 1 unit of x-axis represents 3 units of the data. Now this is not a suitable scale to plot the data values we have. We need a scale on the x-axis that the progression from one unit to the next represents an increase by 2. Hence, selecting an appropriate scale of the graph is vital.