Why should biodegradable and non-biodegradable wastes be discarded in two separate

dust bins?

Biodegradable waste can be broken down by micro-organisms and other living things. They become the part of earth and soil. These wastes can be used as manure or used for composting. While Non- biodegradable do not break down for many years. So they are not environmental friendly.  Eg. plastic , glass etc.
So in order to differentiate these wastes from the biodegradable waste, they are discarded in different dustbins. So that non- biodegradable wastes can be used for recyling.
Green dustbins are used to keep all the biodegradable items and blue dustbins are used for keeing non-biodegradable items or waste.