Whats a qubit?
Any system which has two energy levels can be used to store information. This quantum element for information storage is called a quantum bit or qubit, and unlike regular bits, it can exist in a superposition of both one and zero at the same time. Qubits are the basic building blocks of a quantum computer. Such computers dont exist yet, but are predicted to have enormous computing power for some tasks if they can be built. Trying to decide if and how a quantum computer can be built is one of the main goals of quantum physics today.
