Yield strength is a material property that indicates the maximum stress a material can withstand without undergoing permanent deformation. When a material is subjected to stress, it will initially deform elastically, meaning it can return to its original shape once the stress is removed. However, if the stress exceeds the yield strength, the material will begin to deform plastically, leading to permanent changes in shape. This property is crucial in engineering and construction, as it helps determine how materials will behave under various loads. Understanding yield strength allows engineers to select appropriate materials for structures, ensuring safety and reliability in applications ranging from bridges to buildings.