Volume visualization is a key field of visualization. It is concerned with the representation, manipulation, and rendering of volumetric (voxel-based) data, either sampled, simulated, or modeled. A recently increasing trend in the use of discrete voxel representation for a variety of geometry-based applications, referred to as volume graphics, is apparent. These applications include CAD, simulation, and animation, as well as those that intermix geometric objects with 3D sampled or computed datasets. In these applications, the inherently continuous 3D geometric model is discretized employing voxelization (3D scan conversion) algorithms, which generate a volume buffer (3D raster) of voxels. In order to render these volumetric models and other volumetric data sets in real-time a special-purpose volume engine is imperative. These trends in volume visualization have the potential to revolutionize the field of computer graphics by offering an alternative to the existing surface graphics approach. Volume visualization also promises important breakthroughs in its diverse applications. This talk provides an overview of volume visualization with a focus on volume graphics, the Cube volume engine, the VolVis volume visualization software, and volume visualization applications.