Containing maps showing the distribution of emissions from atomic hydrogen, this is an important reference source for astronomers in many different fields of research.Atomic hydrogen, the principal component of the interstellar medium, was measured over a 5-year period using the 25-meter radio telescope of the NFRA. Displayed in several projections, each map corresponds to a particular velocity interval.A CD-ROM also accompanies the Atlas, and contains the entire dataset of the Leiden/Dwingeloo survey, color images in GIF format, and animations displaying the 3-dimensional data cube.