Tree View Controls 

A tree view control—also known as folder view and an explorer tree—displays a hierarchy of containers. The control includes buttons that expand and collapse the outline, as shown in the following figure. You can use a tree-view control to display the relationship between a set of containers or other hierarchical elements.

Containers are represented by the combination of a text label and icon. Plusses and minuses indicate whether a container is open or closed. Some icons also change states to indicate whether they’re open or closed. For more information, see icon rules.

You can optionally display dotted lines that illustrate the hierarchical relationship of the items in the list.

For more information about organizing an MMC snap-in tree, see Navigation Architecture in the Architecting a Snap-in topic.