Kelley Blue Book is a price guide for used cars, states HowStuffWorks. The guide takes into account condition, mileage and optional equipment on the car. Les Kelley is the founder of the Kelley Blue Book.
Kelley first developed the pricing guide for his own used car lot, sharing it with others before publishing it in 1926, reports HowStuffWorks. It was first used by dealers, and became available to consumers in 1993. An online version was released in 1995. The Kelley family continued to publish the Kelley Blue Book until 2000. The guide was then sold to new owners who continued to publish the book under the Kelley family name.