A step-by-step procedure designed to run on a quantum computer, exploiting superposition, entanglement, and interference to solve problems faster than any known classical algorithm. Key examples include:

• ▸Shor's Algorithm — factorises large integers exponentially faster than classical methods, threatening RSA encryption.
• ▸Grover's Algorithm — searches an unsorted database of N items in ~√N steps, versus N steps classically.
• ▸Quantum Fourier Transform (QFT) — the quantum analogue of the classical Fourier transform; a key subroutine in many quantum algorithms.
• ▸VQE (Variational Quantum Eigensolver) — estimates molecular ground-state energies, with applications in drug discovery and materials science.