What is quantum computing?

Quantum computing is computing based on qubits: units that, exploiting quantum mechanics, can explore multiple states at once instead of being just 0 or 1. For certain problem classes (simulating molecules, optimizing complex systems, factoring large numbers) this promises accelerations impossible for classical computers. It is not a computer "faster at everything": it is radically better at some problems and useless at many others. Today's machines remain noisy and limited in the number of stable qubits, so the gap between the theoretical promise and practical results stays wide: industrial investment is serious and error-correction progress is steady, but no company should expect an operational advantage in the near term. The more concrete risk today is not about raw computing power itself, but about security: a sufficiently mature quantum computer will one day be able to decrypt data encrypted with today's algorithms.

Where things really stand

Current machines are still noisy and limited, and the headline results (the "quantum advantage" demonstrations on purpose-built problems) do not yet translate into advantages on real business problems. The trajectory is serious though: investment is industrial, error-correction progress is steady, and estimates for cryptographically relevant machines have been getting shorter, not longer. Caution about the hype, not about the topic.

What a company should do today

For most companies the honest answer is: no investment in quantum computing, but one concrete security task. The nearest threat is not the quantum computer in your data center: it is the one that, in a few years, will decrypt the encrypted data someone is archiving on you today. The countermove already exists and is called post-quantum cryptography, and the European deadlines are set: national plans by the end of 2026, high-risk systems migrated by 2030, migration complete by 2035. Quantum computing you watch; the cryptographic migration you plan.