Final answer:
Magnetic HDDs use a spinning disk and GMR for data storage and retrieval, while SSDs use flash memory and have no moving parts, offering faster data access and higher reliability.
Step-by-step explanation:
When we compare a magnetic Hard Disk Drive (HDD) and a Solid State Drive (SSD), the main differences lie in their structure and how they process data. Magnetic HDDs utilize a spinning disk coated with magnetic material to store data. The data are read and written by a head that changes the magnetic fields on the disk's surface, historically through induction, but now using giant magnetoresistance (GMR). This technology leverages the change in electrical resistance that is induced by applied magnetic fields in ferromagnetic and nonmagnetic layers.
On the other hand, SSDs do not have moving parts. They store data using flash memory, which is a type of non-volatile memory that can be electrically erased and reprogrammed. The lack of mechanical parts results in faster data access times and higher reliability due to the absence of physical wear and tear. Both of these storage mechanisms are vital in modern day computing, with HDD often being preferred for larger data storage capacity at a lower cost, and SSD for speed and durability.