This document provides an introduction to food safety. It discusses the major causes of foodborne illness including biological, chemical, and physical contamination. Biological contamination, specifically from pathogens like bacteria, viruses, parasites and fungi, poses the biggest threat if foods are left in the temperature danger zone between 41-135°F where pathogens can grow rapidly. Certain foods like meat, dairy and eggs are more vulnerable, or TCS, foods. Proper handling and prevention of cross-contamination are essential to ensuring food safety.