By definition, the Young's Modulus is the ratio of stress to strain, within the limit of propportionality, of any material.
It is also defined  as the  stress in a material  per unit strain.
Hence Young's Modulus is an important tool to compare the load taking capability of various materials.The more the numerical value of Young's modulus, the material can safely take or experiaence more sress for the same quantity of strain.
Hence, if you plot a graph of stress versus strain, you may observe that the numerical value of Young's Modulus is the slope of the plot.