The downloads below are standalone programs that run without other software. The programs access their data (maps, images, figures, and movies) from a file server at UMass, and because they are using the web, require a fast internet connection to run. All DDMs can alternatively access data from a CD, DVD or hard drives, if the data are available in those locations. To view any included movies, both Windows and Mac computers must have the latest QuickTime Player installed (free from Apple for both platforms, at www.apple.com). Computers with less than ~500 MB of free RAM will run these programs very slowly at best.