A location is a node in your model for which fatigue stresses are to be stored. You would typically choose locations that represent points on the structure that would be susceptible to fatigue damage.

An event is a set of stress conditions that occur at different times during a unique stress cycle. See Guidelines for Obtaining Accurate Usage Factors later in this chapter for more information.

A loading is one of the stress conditions that is part of an event.

The alternating stress intensity is a measure of the difference in stress state between any two loadings. The program does not adjust the alternating stress intensity for mean-stress effects.