Young's modulus

Young's modulus, also known as tensile modulus, is a number that tells you how stiff a material is. It is a measure of how much force is required to stretch or compress the material. For example, if you have a metal bar and you pull on it, the Young's modulus will tell you how much force is needed to make the bar longer. So if the Young's modulus is high, it means that you will need a lot of force to stretch the metal. If it is low, then it won't take much force to stretch the metal.