**What Is Data Structure of Binary Tree?**

A binary tree is a type of data structure commonly used in computer science and programming. It is a hierarchical structure that consists of nodes connected by edges or branches.

Each node in a binary tree can have at most two children, referred to as the left child and the right child.

## Structure of a Binary Tree

The basic structure of a binary tree consists of nodes and edges. Each node can have zero, one, or two children.

The topmost node in the tree is called the root node, while the nodes at the bottom are called leaf nodes. The edges represent the connections between the nodes.

Here is an example of a binary tree:

4 / \ 2 6 / \ / \ 1 3 5 7

## Properties of Binary Trees

Binary trees have some interesting properties that make them useful in various applications:

**Root Node:**The topmost node in a binary tree is called the root node. It serves as the starting point for accessing other nodes in the tree.**Leaf Nodes:**Leaf nodes are nodes that do not have any children.They are located at the bottommost level of the tree.

**Internal Nodes:**Internal nodes are nodes that have at least one child. They are located between the root node and leaf nodes.**Parent Node:**A parent node is any node that has at least one child.**Child Nodes:**Child nodes are direct descendants of a parent node.**Depth:**The depth of a node is the number of edges from the root to that particular node.**Height:**The height of a binary tree is the maximum depth of any node in the tree.

## Types of Binary Trees

Binary trees can be categorized into different types based on their structure and properties:

### Full Binary Tree

A full binary tree is a binary tree in which every node has either 0 or 2 children. In other words, every internal node has exactly two children, and all the leaf nodes are at the same level.

### Complete Binary Tree

A complete binary tree is a binary tree in which all levels, except possibly the last, are completely filled, and all nodes are as far left as possible. In a complete binary tree, if any leaf exists at height h, then all leaves must exist at height h or h-1.

### Perfect Binary Tree

A perfect binary tree is a binary tree in which all interior nodes have two children and all leaves have the same depth or same level.

## Applications of Binary Trees

Binary trees have various applications in computer science and programming. Some notable applications include:

__Hierarchical Data Structures:__Binary trees are used to represent hierarchical data structures such as file systems, organization charts, XML/HTML parsing, etc.__Binary Search Trees:__Binary search trees are a type of binary tree that allow efficient searching and insertion operations.__Expression Trees:__Binary trees can be used to represent arithmetic expressions, making it easier to evaluate and manipulate them.__Decision Trees:__Binary trees can be used to represent decision-making processes, such as in machine learning algorithms.

In conclusion, a binary tree is a versatile and widely used data structure that provides an efficient way to organize and store hierarchical data. Understanding the structure and properties of binary trees is essential for various programming tasks and problem-solving scenarios.