The Mayavi project includes two related packages for 3-dimensional visualization: * Mayavi2: A tool for easy and interactive visualization of data. * TVTK: A Traits-based wrapper for the Visualization Toolkit, a popular open-source visualization library. These operate at different levels of abstraction. TVTK manipulates visualization objects, while Mayavi2 lets you operate on your data, and then see the results. Most users either use the Mayavi user interface or program to its scripting interface; you probably don't need to interact with TVTK unless you want to create a new Mayavi module.