The read/write head is a small device used in |disk drives| to detect and manipulate data on magnetic recording media. The head houses a wire coil, which is held in close proximity to the recording surface. The orientation (polarity) of magnetic charges on the recording surface create a small electrical charge in the coil. These electrical signals are read as binary code (zeroes and ones), depending upon the polarity of the charges. The drive may send an electrical charge to the coil as well. This alters the polarity of the charges, and so "writes" to the disk.
