In classical computing, the basic unit of information is represented by a Bit which has definitive states 0 and 1.
In Quantum computing, which draws its inspiration from Quantum mechanics, the basic unit of information is represented in terms of Qubits (Quantum Bits), which can hold all possible states between 0 and 1 simultaneously.
Lets understand three terms which are fundamental to Quantum computing
Superposition
Superposition represents a state in which Quantum particles are in combination of all possible states.
For example, when flipping a coin gives head or tail, its classical computing. But when you are able to see both heads and tails at same time and all possible states in between, the coin is in Superposition.
Entanglement
Entanglement is a state in which Quantum bits (or subatomic particles in physics) are bound with each other so that they can influence each other, irrespective of the distance that separates them.
Quantum interference
Quantum interference is the ability of the Qubits which are in superposition to influence each other.
Reference:
https://azure.microsoft.com/en-us/resources/cloud-computing-dictionary/what-is-quantum-computing
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