A quantum computer is a computing device that uses the phenomena of quantum mechanics (quantum superposition, quantum entanglement) to transmit and process data.

A quantum computer (unlike a conventional one) operates not with bits (which can take on the value of either 0 or 1), but with qubits that have values of both 0 and 1 at the same time.

Theoretically, this allows processing all possible states simultaneously, achieving a significant advantage (quantum superiority ) over ordinary computers in a number of algorithms.

A full-fledged universal quantum computer is still a hypothetical device, the very possibility of building which is associated with a serious development of quantum theory in the field of many particles and complex experiments; developments in this area are associated with the latest discoveries and achievements of modern physics. At the end of the 2010s, only a few experimental systems were practically implemented, executing fixed algorithms of low complexity.