ABSTRACT
The automata network model enables natural complex systems to be described semi-quantitatively. It is also the basis for technological applications in signal processing, pattern recognition and artificial intelligence. This chapter describes a large class of physical systems, known as multiphase systems, which are disordered at the macroscopic level, but some are disordered even at the microscopic level. In fact, the great majority of natural or artificial systems are of a complex nature, and scientists choose more often than not to work on systems simplified to a minimum number of components, which allows him or her to observe "pure" effects. Processors have become very complex, and design time has increased accordingly. The development of software is generally far behind that of hardware, while the impressive capabilities of modern hardware are not being fully exploited. Each processor can be considered an automaton, while the set of processors constitutes a network.
