A quantum computer is any device for
computation that makes direct use of distinctively
quantum mechanical phenomena, such as
superposition and
entanglement, to perform operations on data. In a classical (or conventional) computer, information is stored as
bits; in a quantum computer, it is stored as
qubits (quantum bits). The basic principle of quantum computation is that the quantum properties can be used to represent and structure data, and that quantum mechanisms can be devised and built to perform
operations with this data.
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