An essential part of GIS involves sharing the spatial information that we create. In sharing our work, it is necessary to also document the process, and the strengths and shortcoming of the dataset. Metadata provide an important forum for including this type of information. The following link takes you to some data prepared for the course, which are ESRI GRIDS for the density of tornado tracks per square mile, from the NOAA NWS SVRGIS database. The grids include density by magnitudes, ranging from 1 to 5. Along with the data, a readme file documents the contents of the zipped folder.