Quantum volume is a measure of how large and complicated a quantum computer can be. It is the total number of quantum bits, or "qubits," that a quantum computer can operate with in a given amount of time. Qubits are the basic pieces of information that a quantum computer uses. The larger the quantum volume, the more powerful the quantum computer. For example, a quantum computer with a quantum volume of 10 could be more powerful than one with a quantum volume of 5.