**1. Bits :**

It’s a single unit of information that has a value of either 0 or 1 (off or on, false or true, low or high).

**2. Quantum Bits :**

In quantum computing, a qubit or quantum bit is the basic unit of quantum information—the quantum version of the classical binary bit physically realized with a two-state device. A qubit is a two-state quantum-mechanical system, one of the simplest quantum systems displaying the peculiarity of quantum mechanics.

**Difference between Bits and Qubits in Quantum Computing :**

S.NO | BITS | QUBITS |
---|---|---|

1. | The device computes by manipulating those bits with the help of logical gates (AND, OR, NOT). | The device computes by manipulating those bits with the help of quantum logic gates. |

2. | A classical computer has a memory made up of bits where each bit hold either a one or zero. | A qubits (quantum bits) can hold a one, a zero or crucially a superposition of these. |

3. | Bits are used in classical computers. | Qubits(Quantum bits) are use in quantum computer |

4. | Information is stored in bits, which take the discrete values 0 and 1. | Information is stored in quantum bits, or qbits. A qbit can be in states labelled |0} and |1}, but it can also be in a superposition of these states, a|0} + b|1}, where a and b are complex numbers. If we think of the state of a qbit as a vector, then superposition of states is just vector addition. |

5. | For example, if storing one number takes 64 bits, then storing N numbers takes N times 64 bits. | For example, for every extra qbit you get, you can store twice as many numbers. For example, with 3 qbits, you get coefficients for |000}, |001}, |010}, |011}, |100}, |101}, |110} and |111}. |

6. | Bits are slow. | Qubits are faster. |

7. | Its circuit behaviour based on classical physics. | Its circuit behaviour based on quantum mechanics. |

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