Part 1 Programmers often work with trees, though rarely with family trees. A particularly well-known form of tree is the binary search tree.
Many applications employ binary search trees to store and to retrieve information.
To be concrete, we discuss binary trees that manage information about people. Here we have decided to record the social security number, the name, and two other trees. The latter are like the parent fields of family trees, though the relationship between a node and its left and right trees is not based on family relationships. The choice of false to indicate lack of information is arbitrary. We could have chosen empty again, but false is an equally good and an equally frequent choice that we should become familiar with.