Qubit or quantum bit refers to a key element in a new form of computing called quantum computing that is useful when processing big data. Please refer to our article on quantum computing for more background details. It is important to understand that this new form of computing requires a new type of quantum computer system that is based on circuits that are called qubits. Compared to traditional digital computers we observe that a qubit can not represent just 0 or 1. Instead a qubit can represent 0 and 1 simultanously that in turn is called ‘superposition’ in quantum computing. With this property N qubits can represent 2N bits of information. Hence two qubits are able to represent four states. Another example is that three qubits are able to represent eight states.
In order to perform calculations qubits exploit the above mentioned property ‘superposition’ and jointly work with other qubits via ‘entanglement’. When two quantum systems like an electron or a nucleus interact they become connected and this is called ‘entanglement’. The interesting aspect of this connection is that they retain a very specific correlation in their energy states. These specific correlations in turn represent combinations of 0 and 1 and thus ‘entanglement’ enables qubits to work together. In other words it makes it possible that qubits can even represent multiple combinations of values simultanously instead of just one combination at a time. But when a particular calculation finished qubits can be observed as 0 or 1 values to determine solutions almost like in classical computers today.
Please refer to the following video for more details on this topic: