An updated collection of twelve interactive graphics programs for the Macintosh computer, addressing differential equations and iteration. These versatile programs greatly enhance the understanding of the mathematics in these topics. Qualitative analysis of the pictures leads to quantitative results and even to new mathematics. The MacMath programs encourage experimentation and vastly increase the number of examples to which a student may be quickly exposed. The are also ideal for exploring applications of differential equations and iteration, which roughly speaking form the interface between mathematics and the realworld. This is how mathematics models a changing situation, whether it be physical forces or predator-prey populations. MacMath permits easy investigation of various models, particularly in showing the effects of a change in parameters on ultimate behavior of the system.