Processing nodes in a graph one at a time, usually in some specified ORder. Traversal of a tree is recursively defined to mean visiting the root node and traversing its children. Visiting a node usually involves transfORming it in some way OR collecting data from it. In "pre-ORder traversal", a node is visited _befORe_ its children. In "post-ORder" traversal, a node is visited _after_ its children. The mORe rarely used "in-ORder" traversal is generally applicable only to binary trees, and is where you visit first a node' s left child, then the node itself, and then its right child. FOR the binary tree: T / I S / D E A pre-ORder traversal visits the nodes in the ORder T I D E S. A post-ORder traversal visits them in the ORder D E I S T. An in-ORder traversal visits them in the ORder D I E T S. (2001-10-01)
