Quantum computing and communication are advancing disciplines using the laws of quantum mechanics to manipulate and process information and transmit data, in a fundamentally different way than in a classical system.

The term quantum computing means a form of computation where quantum bits, qubits, are used rather than classical bits. In contrast to classical bits, which either mean 0 or 1, qubits can be in a superposition of states and thus represent a 0 and a 1 at the same time. This fact, together with the entanglement and interference, allows quantum computers to solve some tasks exponentially quicker than classical computers on some tasks, such as factoring large numbers, optimization of complex systems, or simulation of quantum systems. Quantum computers are constructed using technologies such as superconducting circuits, trapped ions, and photonic systems, but as of August 29, 2025 they are still in early development phases.

Quantum Communication entails transmission of information that is secure through the use of quantum states. It is based on such principles as quantum entanglement or no-cloning principle, guaranteeing that any attempt to intercept or measure a quantum signal changes it and thereby identifies eavesdropping. A well-known example is quantum key distribution (QKD), including the BB84 protocol, which enables two parties to exchange encryption keys with perfect security. This is especially applicable to quantum secure communication, whose purpose is to secure data against future quantum computing attack on existing encryption techniques. This field is being pursued with systems such as quantum repeaters and satellite-based QKD (e.g. the Micius satellite in China).

These technologies combined hold revolutionary implications in cryptography, materials science and other areas, but large-scale applications are yet to be developed in practice.