Editor's note: The refuge of golfers, Nirvana fans and wearers of pleated mini-skirts, plaid is fashion's most complicated graphic pattern. It leaves polka-dots and stripes in the dust. It adorns Scottish grooms and pampered West Highland terriers. And it has a way of seeming like more than the sum of its parts. It's nothing more than horizontal and vertical lines that intersect at 90 degree angles, yet it comes to represent entire clans and certain boarding schools. Now, go find your favorite plaid in this great collection!