This state contains a coefficient for the likelihood of being zero and a coefficient for the likelihood of being one.
In traditional classical computing, our information takes the form of classical information, with bits taking the value of either zero or one, carefully. Quantum mechanics, however, is not so simple: a value can be both a zero and a one in a probabilistic, unknown state until measured. This state contains a coefficient for the likelihood of being zero and a coefficient for the likelihood of being one. Once the qubit is observed, the value discreetly becomes either a zero or a one. In practice, these qubits take the form of some subatomic particles that exhibit the probabilistic properties of quantum mechanics, such as an electron or photon. Furthermore, several particles can become coupled in probabilistic outcomes in a phenomenon called quantum entanglement, in which the outcome of the whole is no longer simply dependent on the outcome of independent parts.