In 1967 Andrew J. Viterbi
published a very important paper called ``Error Bounds for Convolutional Codes and an Asymptotically Optimal Decoding Algorithm
'' in IEEE Transactions on Information Theory
volume 13 pages 260--269.
The paper (which is not recommended reading for newbies in the area) contained a proof that given a Model of the expected communication over a Noisy Channel and a stream of signals received over that channel then a particular kind of search could guarantee to predict optimally the signals as sent. This amounted to an optimal noise suppression algorithm and has become known as Viterbi search.
Viterbi search is widely used in modern speech recognition, handwriting recognition and natural language processing systems.
This has been a The Nodeshell Rescue Team production.