A quantum bit, or qubit, is the basic unit of information in quantum computing. Unlike a classical bit, which can be either 0 or 1, a qubit can exist in multiple states simultaneously due to a property called superposition. This allows quantum computers to process a vast amount of information more efficiently than traditional computers. Additionally, qubits can be entangled, meaning the state of one qubit is directly related to the state of another, regardless of the distance between them. This phenomenon, known as quantum entanglement, enables complex computations and enhances the power of quantum algorithms, making them potentially much faster for certain tasks.