tree structure(A tree structure or tree diagram is a way of representing the hierarchical nature of a structure in a graphical form. It is named a "tree structure" because the classic representation resembles a tree, even though the chart is generally upside down compared to an actual tree, with the "part of the plant in the ground" at the top and the "leaves" at the bottom: A form of hypertext that predates the World Wide Web, it is arranged in a tree structure.
• You control the layout in a tree structure on the left hand side of the screen. (ODE)wikipedia.orgAlexander Demidov)
