Resumen
Evolvable hardware (EHW) refers to one particular type of hardware whose architecture, structure and functions change dynamically and autonomously in order to improve its performance in performing certain tasks. The emergence of this new field has been influenced profoundly by the progress in reconfigurable hardware and evolutionary computation. Traditional hardware is notorious for its inflexibility. It is impossible to change the hardware's structure and functions once it is made. However, most real-world problems are not fixed. They change with time. In order to deal with these problems efficiently and effectively, different hardware structures are necessary. EHW provides an ideal approach making hardware "soft" by adapting the hardware structure to a problem dynamically. There have been some concerns in recent years over the black-box nature of EHW, since it is often very difficult to analyze and understand circuits evolved by evolutionary algorithms. These concerns are natural and appear in other bio-.inspired systems as well, such as in artificial neural networks.