Computational theory is quite important for CS, yet traditional courses are taught in nonvisual manners that are frustrating to students, with no visualization to relate to or feedback on problems. There have been several software tools that attempt to change that, usually focusing on only one specific concept. JFLAP covers many topics in a visual and interactive manner. JFLAP creates a hands-on FLA course when combined with an automata theory textbook, useful in and out of class, to aid in understanding of theory concepts.
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