Character recognition algorithms generally fall inot one of two categories: neural network (NN) or Hidden Markov Models HMM).  We adopt the perspective from HMM's , namely, that character recognition is an example of a noisy channel problem.  The noisy channel problem assumes that a  standard form of information is being transmitted over a noisy channel and that the noisy channel will distort the information received. The Viterbi algorithm , employing probabilistic methods, determines the most likely form of the original data.