Trees and Binary Trees

This lesson covers trees and binary trees — hierarchical data structures that organise data in a parent-child relationship. Trees are used in file systems, databases, decision-making, and expression parsing.

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What is a Tree?

A tree is a non-linear, hierarchical data structure consisting of nodes connected by edges. It has the following properties:

• There is exactly one root node (the top node with no parent).
• Every other node has exactly one parent.
• Nodes can have zero or more children.
• A node with no children is called a leaf (or terminal node).

Key Terminology