Information is recorded in a computer on magnetic tapes, magnetic tapes and hard disks using an electromagnet, changes in the magnetic field of which determine the magnetization of the carrier in accordance with the information. At the beginning of the creation of computers, the recording of information on magnetic media was very widespread. Even the RAM of the first computers was implemented on small ferromagnetic cores, each of which stored 1 bit of information. In modern computers, magnetic tape is practically not used, since it requires access to information for a long time to write on it. Therefore, recording is made on hard disks made of ferromagnetic material, rotating at great speed.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.