(Tree is a non-linear data structure, it exists widely in the objective world, for example, the family tree of people's society and various social organizations can be represented by trees. The most commonly used are the tree and the binary tree, during which the binary tree is more effective. Why do you say this? Because most of the operations can be transformed into a father, a left son and a right son, and the operations on the binary tree are simpler.
Data Structures and Algorithms--Lao Luo's Colorful Liuhe.CHM)