lets you develop Turing Machines, which are imaginary devices that formed the framework for modern computer science. The Turing Machine has become the foundation of the modern theory of computation and computability. The inventor, Alan Turing, laid the theoretical framework for modern computer science by showing that computation could be satisfied by a machine that consisted of a tape of unlimited length with little square cells, and a device with a finite number of states that could read symbols from the tape.
Visual Turing is a tool which helps you to develop Turing Machines. It is supported the entire process of the development, from the designing of the graph (the "program" of the machine, which is made fully visual), to running the program, including stepping out, over and back.