A: Yield strength: The stress value at which a material begins to undergo permanent deformation (yield). In structural design, this is the most critical parameter because it determines the maximum load a structure can withstand under normal operating conditions without permanent damage.

Tensile strength: The maximum stress a material can withstand before breaking. It represents the material's ultimate load-bearing capacity.

Simply put, yield strength relates to safety and service life, while tensile strength relates to the ultimate limit of failure.