Plato's theory of Forms

A quick Googling Adam seems to indicate that it relates to the reality of the abstract

http://en.wikipedia.org/wiki/Theory_of_Forms

Maybe World of Forms v World of Substances. I hope someone better versed than your Average Clod (me) will step into explain

For Plato there are really two worlds in existence -- the real and the actual. When you look at the chair you were just sitting in, you are not seeing a real chair, just the actualization of the ideal of chairness. What you perceive through your senses, for Plato, is just a form of the real world, which is perfection itself but not available to us poor humans on a sensuous level.

(The Wikipedia article which dale linked is okay, but it makes a fairly simple concept sound unnecessarily complex.)

Thanks Andy for saving me the entire morn Googling. Agreed Wiki's needs to be restated in terms suitable for the Average Clod (me)

My immediate reaction however is that Plato's idea is so vague and open to interpretation as to be essentially meaningless