What is a redox reaction? Explain its uses.

(N/A) redox reaction is a chemical reaction in which the oxidation numbers of the reactants change.
It is a combination of oxidation and reduction processes.
Uses:
$i$. These reactions are extensively used in pharmaceutical,biological,industrial,metallurgical,and agricultural sectors.
$ii$. They are used for professional purposes and in various types of fuels.
$iii$. They are used in the industrial preparation of $NaOH$.
$iv$. They are essential for the operation of dry and wet batteries.
$v$. They are used in electrochemical processes for the extraction of highly reactive metals and non-metals.
$vi$. They are used in the production of hydrogen.
$vii$. They are involved in the chemical processes leading to the development of the ozone hole in the ozone layer.