Ken Levasseur, Al Doerr, Michiel Smid, Oscar Levin, Charles M. Grinstead, J. Laurie Snell, Eric Lehman, F. Thomson Leighton, Albert R Meyer, Jeff Erickson, Kenneth P. Bogart, Carol Chritchlow, David Eck, OpenDSA Project, L.J. Miller
One understands a set of objects completely only if the structure of that set is made clear by the interrelationships between its elements. For example, the individuals in a crowd can be compared by height, by age, or through any number of other criteria. In mathematics, such comparisons are called relations. The goal of this chapter is to develop the language, tools, and concepts of relations.