Traversing (or walking) a tree is the process of visiting all the nodes of a tree and performing an operation at each node. However, how should we do this? Should we start from the top of the tree or from the bottom? From the left-hand or the right-hand side? There are three different approaches that can be used to visit all the nodes in a tree: in-order, pre-order, and post-order.
In the following sections, we will dive into the uses and implementations of these three types of tree traversals.