This document discusses various categories of food hazards. It divides hazards into three main groups: expected hazards defined by Codex Alimentarius including biological, chemical and physical hazards; hidden hazards in the food chain such as irradiated food and household chemicals; and insidious hazards including food handlers' mental health and ergonomic issues as well as electronic and long-term hazards like genetically modified food. The document emphasizes the importance of considering all categories of hazards, including insidious ones, during hazard analysis in food safety systems like HACCP to improve food safety.