Data Structures

4. Tree: A data structure whose nodes link back to their parent nodes and might also link to children nodes.

   Because each node can be either a child or a parent of some node, the tree establishes a hierarchical relation between the nodes. The node in the tree that doesn't have a parent is called the root.

   Different types of trees include: binary trees (in which each node can have up to 2 children), general trees (in which there is no limitation on the number of children a node can have), and binary search trees (in which the left child has a value that is less than or equal to the value of the right child.)

We will encounter trees when talking about the file system (which contains files inside folders inside folders, etc.) and CPU-scheduling algorithms.