Chlorination of water is done to

Chlorination disinfects water by killing microbes such as bacteria and viruses.

It does not soften water, so hardness-causing calcium and magnesium remain.

It adds no beneficial salts and is not meant to raise salt content.

Turbidity from suspended particles is reduced by filtration, not chlorination.

Chlorine leaves a residual that keeps water safe through the distribution network.

Excess chlorine can form disinfection by-products like trihalomethanes.