What is the function of mechanical hard disk?

Mechanical hard disk is a traditional common hard disk, which is mainly composed of disk, magnetic head, disk spindle, control motor, magnetic head controller, data converter, interface and cache. The magnetic head can move along the radial direction of the disk, and the disk rotates at a high speed of several thousand revolutions per minute, so that the magnetic head can be positioned at the designated position of the disk to read and write data. The information is written on the disk by the electromagnetic current near the magnetic surface of the magnetic head, which in turn can read the information. Hard disk is a precision device, and dust is its enemy, so the air entering the hard disk must be filtered.