Explain the working principle of the hard disk drive?

Answer 1

A hard disk uses platters, round discs that are coated with a special media that is designed to store data in magnetic patterns. These discs rotate so that heads, electromagnetic read/write devices, can either record data onto the platters or read what the platters already contain. Each platter has tracks which is then broken down into sectors which is where pieces of data is actually recorded.

Answer 2

that is a magnetic property of the material content included in the hard disc

Answer 3

this is most important part of computer's is help to work computer.