The word "permaculture" was first used in the mid 70's by David Holmgren, a young Australian ecologist, and his associate, Bill Mollison. It is a contraction of "permanent agriculture" or "permanent culture."
The concept of permaculture is best defined in Bill Mollison's book entitled PERMACULTURE - A Designer's Manual, Bill defines permaculture as: "Permaculture (permanent agriculture) is the conscious design and maintenance of agriculturally productive ecosystems which have the diversity, stability, and resilience of natural ecosystems. It is the harmonious integration of landscape and people providing their food, energy, shelter, and other material and non-material needs in a sustainable way. Without permanent agriculture there is no possibility of a stable social order.
Permaculture design is a system of assembling conceptual, material, and strategic components in a pattern which functions to benefit life in all its forms."
In other words it is the study of nature and the application of nature to all agricultural practices. I would also suggest that it goes further than just agricultural practices. Gardening, landscaping, water management, urban development, rural housing and recycling of waste products should also be included.
Bill's book is a blueprint for those who wish to build a sustainable environment on which to live a self-sufficient lifestyle. (I am not here to promote anyone's books, but I do believe that Bill's book is essential to anyone considering this lifestyle.)