Complex sentence: It measures the force (per unit area) that is needed to stretch (or compress) a material sample.Do not confuse this with'elastic modulus' which is the geometric property of a cross-sectional area.
Split into simpler sentences: It measures the force (per unit area) that is needed to stretch (or compress) a material sample. It is not to be confused with'elastic modulus' which is the geometric property of a cross-sectional area.