Can you explain what a binary tree is and how it is structured?

A binary tree is a data structure in which each node has at most two children: left and right. It is commonly used to organize data hierarchically, enabling efficient search, insertion, and deletion operations.

Each node contains a value and references to its children. For example, in a binary search tree (BST), the left child contains a value less than the parent, and the right child contains a value greater.

An example of a binary tree node in Swift:

class TreeNode {
    var value: Int
    var left: TreeNode?
    var right: TreeNode?

    init(_ value: Int) {
        self.value = value
    }
}

Such a tree allows for efficient organization and processing of data, for example, for searching or sorting.