Although fatigue is commonly experienced in many highly demanding occupations (e.g., military, first responders, etc.), it is poorly defined. Fatigue can strongly affect occupational performance by negatively influencing the ability to interact with the world by altering the capacity to think, move, feel, see, and speak. The first step in fatigue risk management strategies is to establish a context. The context of this narrative review is to specifically describe and discuss the 6 overarching types of occupational fatigue: cognitive, physical, burnout, emotional, visual, and vocal fatigue, and how each affects varying occupations. Furthermore, fatigue type can be influenced by several intrinsic factors, such as sleep deprivation, circadian alignment, ultradian process, sleep homeostasis, and health factors. Similarly, extrinsic factors influence fatigue, such as workload, shift work, and environmental issues. Understanding the types and contributors to occupational fatigue may help clarify the context of occupational fatigue and serve to guide future occupational fatigue management.