Oxidation and reduction

Oxidation :- oxidation is loss of electron, adding oxygen or removal of hydrogen from any element 

Example:- C +O2 —> CO2

In this expalme oxygen is adding in carbon. In this example C (carbon is oxydising agent)

Reduction :- reduction is gain of electron, adding of hydrogen or removal of oxygen.

Example:- Fe2O3 + 3CO —> 2Fe + 3CO2

In this example Fe2O3 get in reduction process as it losses oxygen atoms.