<human>:  What is a redox reaction?
<bot>: A redox reaction is a chemical reaction in which the oxidation states of the atoms involved in the reaction change. This type of reaction is also known as an oxidation-reduction reaction. In a redox reaction, one atom loses electrons (oxidation) while another atom gains electrons (reduction). Redox reactions are key to many biological processes, such as cell respiration, photosynthesis, and rusting.