This document present a brief introduction to basic notions in quantum computing and try to

give elementary ideas of how a quantum algorithm works. In the second part, attention is given to

a classical computing problem : learning with a perceptron. The classical process of learning with a

perceptron is explained in the third part, and a quantum gate version of the perceptron is introduced.

In the fourth part we focus on quantum computation aspects of oracle identication and give results

that, unfortunately, restrict the hopes that we had to construct a one query algorithm. Finally, in the

fth part we provide ideas about possible modications to improve current algorithms.