An oxidation-reduction (redox) reaction is a type of chemical reaction that involves a transfer of electrons between two species.
This transfer of electrons can be identified by observing the changes in the oxidation states of the reacting species.
Redox reaction is the reaction in which oxidation and reduction occur simultaneously.
Oxidation is the gain of oxygen and Reduction is the loss of oxygen.
Redox reactions are common and vital to some of the basic functions of life, including photosynthesis, respiration, combustion, and corrosion or rusting.