Tractography of cerebral white matter fibers based on diffusion tensor imaging (DTI) is a recent magnetic resonance technique that enables the visualization of the anatomy and integrity of white matter tracts. This article aims to provide two- and three-dimensional representations of the main white matter tracts in the brain from high spatial resolution DTI data and to explain the physical basis of the technique, its main clinical applications, and how we use it. We provide examples of the use of DTI in the study of the corpus callosum, the anterior white commissure, the corticospinal tract, the limbic system, the long association fibers, the cerebellar peduncles, and the optic tract.