Simple tension refers to the force applied to an object, such as a rope or shaft, where forces act away from each other, creating tension throughout the material. This tension is uniform along the length of the object until it reaches an anchor point. In contrast, compression forces act towards each other, indicating that simple tension does not involve any compression. The discussion emphasizes the distinction between tensile and compressive forces in structural contexts. Understanding these concepts is crucial for analyzing material behavior under different load conditions.