In traditional computers, information is encoded in bits represented as either a zero or one. But in quantum computers, information is encoded in quantum bits (or qubits) that can be either, or both at the same time. That drastically expands their potential computing power, meaning they could tackle problems beyond the scope of regular computers.
Last year, for instance, a Chinese quantum computer called Jiuzhang apparently performed a calculation in 200 seconds that would take a regular supercomputer 2.5 billion years to complete.
But the challenge with quantum computing is that these qubits are sensitive to interference from the environment, with tiny fluctuations in temperature or vibrations threatening to scramble the data. That makes it difficult to transmit quantum information over long distances.