Quantum computing differs from classical computing in that it uses quantum bits or qubits, which can exist in a superposition of both 0 and 1 simultaneously, rather than being strictly 0 or 1 as in classical bits. Additionally, qubits are subject to entanglement and quantum interference, which allows quantum computers to solve certain types of problems exponentially faster than classical computers.
Qiskit is an open-source framework developed by IBM to allow users to interact with quantum computers. It provides tools to create quantum circuits, execute them on simulators, and even run them on actual quantum computers available via IBM Quantum Experience.