What are Buffer solution ? Explain types of Buffer solutions.

Buffer solutions : The solutions which resists the change in its pH values by the addition of
small amount of strong acid and strong base (or) dilution is known as “Buffer solutions”.
(or)
A solution reserves its acidity or alkalinity (basicity) is known as buffer solution.
Buffer solution are classified into two types
a) Acidic Buffer
b) Basic Buffer
Acidic Buffer : It is prepared by the Mixture of weak acid and its salt of strong base is known as acidic buffer.
Eg : $\underset{\left(\mathrm{weakacid}\right)}{{\mathrm{CH}}_3\mathrm{COOH}}+\underset{(\mathrm{salt} \mathrm{of} \mathrm{strong} \mathrm{base})}{{\mathrm{CH}}_3\mathrm{COONa}}$
Basic Buffer : It is prepared by the mixture of weak base and its salt of strong acid is known
as basic buffer.
Eg : $\underset{(\mathrm{Weak} \mathrm{base})}{{\mathrm{NH}}_4\mathrm{OH}}+\underset{(\mathrm{salt} \mathrm{of} \mathrm{strong} \mathrm{acid})}{{\mathrm{NH}}_4\mathrm{Cl}}$