Quantum computing studies theoretical computation systems (quantum computers) that make direct use of quantum-mechanical phenomena, such as superposition and entanglement, to perform operations on data.
Quantum computers are different from binary digital electronic computers based on transistors.
Whereas common digital computing requires that the data be encoded into binary digits (bits), each of which is always in one of two definite states (0 or 1), quantum computation uses quantum bits, which can be in superpositions of states.
A linear superposition of the "basis states" |0> and |1> . Here|0> is the Dirac notation for the quantum state that will always give the result 0 when converted to classical logic by a measurement. Likewise |1> is the state that will always convert to 1.
superposition says a particle can be in two locations, or in the same location but can be spinning in opposite directions at the same time. In fact, it can be in many states at the same time.
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