This document discusses antioxidants, what they are, how they work, and why they are important. It defines antioxidants as molecules that prevent oxidation and free radical damage by donating or accepting electrons from free radicals. Various categories of antioxidants are described, along with tests used to measure antioxidant capacity. The document emphasizes that antioxidants play an important role in health by reducing free radical damage linked to diseases, and recommends including antioxidant-rich foods like fruits and vegetables in the diet.