Wastes are broadly classified into how many types?

Wastes are those substances that are discarded after primary use and are no longer needed for the same purpose.

They are broadly classified into two types. These are biodegradable and non-biodegradable wastes. 

Biodegradable waste can be broken down into simpler compounds by the action of microorganisms whereas, non-biodegradable waste cannot be acted upon by microorganisms and may pose a threat to the environment.