Tree

A tree structure is a type of categorization of data into categories and subcategories. Think of starting at the root (or trunk) of the tree – that’s the main category, for example: Party Goods. From the root, the data branches into subcategories: Balloons, Tableware, and Decorations. Then Balloons splits into subcategories: Mylar and Latex. The point where a category splits is called a node and so are the final subcategories (the ends of the branches). The actual products themselves (the item records) are assigned to nodes. Every record is assigned to one, and only one, node. Nodes can have multiple records assigned to them.