Colloids play a very significant role in nature and in our daily life. Some of the important applications of colloids are discussed below:
 1) Medicines:
Medicines in colloidal form are easily adsorbed by the body tissues and hence are more effective.

2) Sewage disposal:

Colloidal particles of the dirt, mud etc. carry electric charge, hence when sewage water is passed through the plates kept at a high potential, the colloidal particles are coagulated due to electrophoresis and the suspended matter gets removed
 3) Purification of water:
The precipitation of colloidal impurities present in water can be done by adding certain electrolytes like alum etc. the negatively charged colloidal particles of impurities get neutralized by the Al3+ ions and settle down and pure water can be decanted off.
 4) Cleansing action of soap:
Soap solution is colloidal in nature. It removes the dirt particles either by adsorption or by emulsifying the greasy matter sticking to the cloth.

5) Photography:
A colloidal solution of silver bromide in gelatin is applied on glass plates or celluloid films or paper to from sensitive plates in photography.

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