What is one common use of magnets in modern technology?

The use of magnets in modern technology is prominently exemplified by their role in storing and retrieving data in hard drives. Hard drives utilize magnetic storage media to retain information. When data is written to the hard drive, it modifies the magnetic state of specific areas on a disk, which allows the information to be stored. When this data needs to be retrieved, read/write heads use the magnetic properties of these disks to access the specific data quickly and efficiently.

In contrast, timekeeping in clocks typically relies on mechanical movements or electronic oscillators, not magnetic fields. Temperature measurement is carried out using thermocouples or thermistors, which do not involve magnets. Lastly, although certain types of light bulbs, such as some fluorescent bulbs, may use electromagnetic fields to operate, traditional incandescent bulbs and LED technology primarily rely on electrical circuits rather than magnetic forces for their light generation. Therefore, the application of magnets in hard drives serves as a fundamental component of data storage technology in modern computing.