Hard disk drives have several key components including disk platters, read/write heads, an actuator mechanism, spindle motor, logic board, and cables. Disk platters are coated with a magnetic recording medium, which were originally iron oxide but now include thinner, harder materials like glass. Modern drives use glass or glass-ceramic platters coated with thin-film, oxide, or anti-ferromagnetically coupled media. Read/write heads read and write data to the magnetic surfaces of spinning disk platters.