Quantum computing is a fast-emerging area of computer science that is upending the foundations of cybersecurity. It’s set to change how we secure our everyday communications, process credit cards, store data, and securely connect to websites. But it’s also likely to disrupt modern security as we know it. What is quantum computing? Conventional computing is based on a simple binary number concept developed for the first computers designed after World War II. Every computer instruction is translated into a sequence of 0s or 1s. In quantum computing, meanwhile, instructions can be in a state of 0 and 1 at the same time. This allows them to work on millions of computations in parallel, exponentially speeding up the time it takes to process a task. This new approach to computing is predicted to radically change areas such as drug discovery, stock market prediction, gene sequencing, and, of course, cryptography—a key component.