This document discusses different types of biodegradable plastics, including oxo-biodegradable plastics made from petroleum or organic carbon and hydro-biodegradable plastics that are synthetic polyesters or contain some renewable organic carbon. It notes that biodegradable plastics are engineered to fully degrade and biodegrade after use, returning the carbon to the natural carbon cycle. The document also outlines options for managing biodegradable plastics through recycling, composting, or landfilling and questions whether zero waste is possible by diverting compostable plastics from landfills.