Describing colours with words is always a difficult proposition. (We are continually being confronted by this fact when we try to explain to customers on the phone the differences between various greens we need to hire a poet perhaps!) For this reason, people who work with colour use colour systems in order to exactly define a colour. Various branches have over time come to accept certain systems as being the standard. When working with these systems, things like colour fans and books are among the essential aids. Because such aids are not so easy to get your hands on (with the result that we are continually being asked for them ), we have decided to add books and fans from the most well known colour systems to our product line.