Quantum computing is a distant, albeit intensely pursued, goal. To understand its allure, consider how much more information one can process by replacing the classical bit, representing either a 1 or a 0, with a two‐state quantum system, such as an ion having two energy levels. This system, called a qubit, might be in either of its two states, representing a 1 or a 0, but it can also be in a superposition of its two states.