Cone Trees are a 3D visualization technique for hierarchical information structures, developed by George G. Robertson, Jock D. Mackinlay, and Stuart K. Card. The technique uses interactive animation and 3D visualization to help users manage and access large information spaces. The hierarchy is presented in 3D to maximize screen space usage and enable visualization of the whole structure. Interactive animation reduces cognitive load by exploiting the human perceptual system. The Cone Tree is implemented in a prototype system called the Information Visualizer. It is used to visualize hierarchical information structures, with each node represented as a 3x5 index card. The hierarchy is laid out uniformly in three dimensions, with the top of the hierarchy near the ceiling and children evenly spaced along the base. Each layer has cones of the same height, and the base diameters are reduced to fit the room width. The body of each cone is shaded transparently to allow visibility of cones behind it. When a node is selected, the Cone Tree rotates so that the selected node and each node in the path from the selected node up to the top are brought to the front and highlighted. The rotations are animated to allow the user to see the transformation at a rate the perceptual system can track. The display of node text is limited to the selected path, as it does not fit the aspect ratio of the cards well. An alternative layout, called the Cam Tree, is horizontally oriented and displays text for each node. Interactive animation helps reduce cognitive load by allowing the perceptual system to track rotations. The 3D perspective view of Cone Trees provides a fisheye view of the information, with the selected path brighter, closer, and larger than other paths. The user perception of 3D depth is enhanced by size changes, lighting cues, and shadows of cones and nodes cast onto the floor. Cone Trees are used for viewing parts of trees, restructuring trees dynamically, and searching through underlying information. Gardening operations allow users to prune and grow the view of the tree, making it easier to manage and understand large, complex hierarchies. Techniques for directly rearranging the Cone Tree are used for dynamic changes in hierarchy structure. Applications of Cone Trees include file browsers, organizational structure browsers, and company operating plans. The technique is effective for unbalanced hierarchies and can be used for a wide range of applications, including software module management, object-oriented class browsers, document management, and local area network browsers. The use of interactive animation and 3D visualization is effective in improving the management and access of large information spaces. However, there are limits to the size of the hierarchy that can be effectively displayed. The technique is particularly effective for unbalanced hierarchies and can be used for a wide range of applications. Future studies are needed to evaluate the effectiveness of 3D visualization in improving information management and access.Cone Trees are a 3D visualization technique for hierarchical information structures, developed by George G. Robertson, Jock D. Mackinlay, and Stuart K. Card. The technique uses interactive animation and 3D visualization to help users manage and access large information spaces. The hierarchy is presented in 3D to maximize screen space usage and enable visualization of the whole structure. Interactive animation reduces cognitive load by exploiting the human perceptual system. The Cone Tree is implemented in a prototype system called the Information Visualizer. It is used to visualize hierarchical information structures, with each node represented as a 3x5 index card. The hierarchy is laid out uniformly in three dimensions, with the top of the hierarchy near the ceiling and children evenly spaced along the base. Each layer has cones of the same height, and the base diameters are reduced to fit the room width. The body of each cone is shaded transparently to allow visibility of cones behind it. When a node is selected, the Cone Tree rotates so that the selected node and each node in the path from the selected node up to the top are brought to the front and highlighted. The rotations are animated to allow the user to see the transformation at a rate the perceptual system can track. The display of node text is limited to the selected path, as it does not fit the aspect ratio of the cards well. An alternative layout, called the Cam Tree, is horizontally oriented and displays text for each node. Interactive animation helps reduce cognitive load by allowing the perceptual system to track rotations. The 3D perspective view of Cone Trees provides a fisheye view of the information, with the selected path brighter, closer, and larger than other paths. The user perception of 3D depth is enhanced by size changes, lighting cues, and shadows of cones and nodes cast onto the floor. Cone Trees are used for viewing parts of trees, restructuring trees dynamically, and searching through underlying information. Gardening operations allow users to prune and grow the view of the tree, making it easier to manage and understand large, complex hierarchies. Techniques for directly rearranging the Cone Tree are used for dynamic changes in hierarchy structure. Applications of Cone Trees include file browsers, organizational structure browsers, and company operating plans. The technique is effective for unbalanced hierarchies and can be used for a wide range of applications, including software module management, object-oriented class browsers, document management, and local area network browsers. The use of interactive animation and 3D visualization is effective in improving the management and access of large information spaces. However, there are limits to the size of the hierarchy that can be effectively displayed. The technique is particularly effective for unbalanced hierarchies and can be used for a wide range of applications. Future studies are needed to evaluate the effectiveness of 3D visualization in improving information management and access.