Permaculture is a design system that focuses on sustainable agriculture and human settlements. It has three core ethics: care for the earth, care for people, and share the surplus. Some key principles of permaculture design include observing patterns in nature, catching and storing energy, obtaining a yield, applying self-regulation, using renewable resources, producing no waste, designing from patterns to details, integrating rather than segregating elements, using small and slow solutions, valuing diversity, using edges and marginal areas, and creatively responding to change.