Quantum computing utilizes quantum bits (qubits) that can represent both 0 and 1 simultaneously due to superposition, unlike classical bits that are either 0 or 1. This enables quantum computers to process complex calculations exponentially faster than classical ones. Potential applications include drug discovery by simulating molecular interactions, optimizing supply chains, solving complex cryptographic problems, and advancing artificial intelligence. Despite its promise, challenges like error correction and scalable hardware must be overcome for widespread use.