Permaculture was a word we had always heard. There was always a Permaculture stall or area at most festivals we went too but we never really knew the details. Growing things and saving the planet was all we knew about it.
So instead of trying to explain it myself and going to give you some useful links.

http://www.spiralseed.co.uk/permaculture/


http://www.theecologist.org/green_green_living/gardening/451581/a_beginners_guide_to_permaculture_gardening.html