Qubits
A standard computer processor is binary meaning that each transistor can only exist in two states either 1 or 0, on or off.
While a Quantum Computer uses Quantum Bits or Qubits. A qubit can theoretically exist in an infinite number of states due to the 3 dimensional nature of the states.
This means that you can store and process a huge amount of information with only a couple of bits. This is the basic fact about Quantum computers that makes them so efficient.
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