TreeView Professional is a simple-to-use but powerful multi-level tree menu. An unlimited number of 'pages' can be grouped into an unlimited number of 'folders and subfolders' expanding to a possible 8 levels. Both folders and pages can act as links, and each entry on the menu can update 4 different frames at once. A click opens the URL(s) specified for the link, and/or expands or collapses the corresponding portion of the tree if the clicked item was a folder.

To ensure that the applet can fit into a compact space, horizontal and vertical scrollbars are added and removed as necessary. The font and a multitude of colors are user-definable. The tree is also keyboard-operable: use arrow keys to move around and to expand and collapse folders, and Enter to select.

TreeView Professional offers a choice of two modes. In 'images' mode, folders and pages are given matching icons alongside the traditional tree-outline and text labels. You can specify a single image file containing the three default images to use for all items, and optionally override these images by specifying individual images to be used for any item. In 'plain' mode, only the outline and text labels are shown.