What is the difference between yield strength and yield stress, and how do they affect the mechanical properties of a material?

Yield strength and yield stress both measure the point at which a material begins to deform permanently under stress. Yield strength is the force required to cause this deformation, while yield stress is the pressure needed. These properties affect how a material behaves under load, determining its ability to withstand forces without breaking or bending. Materials with higher yield strength and yield stress are generally stronger and more durable.