What is an edge (edge) in a tree?

An edge is a connection between two nodes in a tree: between a parent and its child.

Formally:

An edge is a directed connection of the form

It shows how nodes are connected to each other and defines the structure of the tree.

Example:

Here there are two edges:

• A → B
• A → C

Properties:

• If a tree has n nodes, it always has exactly n - 1 edges.
• Edges can be used to describe paths - sequences of moves from one node to another.

Summary: An edge is the "connection" or "branch" that links nodes together and makes a tree a hierarchical structure rather than just a set of data.