As someone who has been involved with morris for nearly 40 years - Dancing, teaching and leading teams in the traditional villages of Adderbury & Kirtlington, Oxfordshire; It is a HUGE subject.
I suggest you look at:
http://en.wikipedia.org/wiki/Morris_dance

I am NO good at blue clicky things on Mudcat!

This site is very good and leads you to other places.

Tim Radford