A tree diagram is a visual representation used to illustrate the relationships between different elements in a structured way. It resembles a tree, with a main trunk representing a primary concept and branches that extend to show related ideas or categories. This format helps in organizing information hierarchically, making it easier to understand complex relationships. Tree diagrams are commonly used in various fields, including mathematics, computer science, and decision-making. They can represent everything from family trees to organizational structures and probability outcomes. By breaking down information into simpler parts, tree diagrams facilitate clearer analysis and communication.