Quantum computers are devices that use the principles of quantum mechanics to perform calculations that are impossible or impractical for classical computers. Quantum computers have the potential to revolutionize many fields of science and technology, such as cryptography, artificial intelligence, drug discovery, and optimization. However, quantum computers also face many challenges and limitations, one of which is the need to operate at extremely low temperatures, close to absolute zero. In this article, we will explain why quantum computers need to be cooled to near zero temperatures, and how this is achieved in practice. The Challenge of Quantum Decoherence One of the main reasons why quantum computers need to be cooled to near zero temperatures is to prevent quantum decoherence. Quantum decoherence is the process by which a quantum system loses its quantum properties and behaves like a classical system due to interactions with its environment. Quantum computers rely on quantum bits...