Use of visual tools in distance teaching of computational models

We present visual interactive tools for distance teaching in course "Automata Theory and Formal Languages" (AFL) that explores mathematical models of computation. Using the tools, students can interactively explore the various classes of automata and grammars, their properties, expressive power, and transformations. The tools help to get prompt answers to typical questions, and to gain a better sense of concepts that would otherwise remain purely formal. This is especially important in distance education, where traditional difficulties in learning theoretical material become even more severe. Our tools address cognitive and communication aspects of asynchronous learning process. The need in such tools has been recently widely recognized.