In recent years there has been a great development of artificial intelligence (AI). From agriculture to finance passing through healthcare, the potential advantages of using these algorithms are extremely high. Our life is influenced daily by AI decisions, just think of the recommendation systems for films and TV series, suggestions for purchases in an e-commerce or even the mechanisms of targeted advertising. But there is an important distinction to be made, although the performance of an artificial intelligence is very high there are areas in which for various reasons the AI decision cannot be accepted. The reason for this difference is due to the construction of artificial intelligence, they work like black boxes, take an input and return an output, the results provided are often excellent, there is no knowing why a decision has been made, a fundamental element in many sectors.