This help file is organized according to the main functions of DynaSys. There is a major section on Input and Output, another on Typing Equations, and a third concerning the use of the various types of displays that are available. Each topic within these groups has three subtopics. The first tells about the capabilities of the feature, the second discusses the actual use of the feature, and the third lists the default behaviors of the feature. We have tried to provide at least one example to illustrate each feature.