There are std. HD and then there ara SSD(sold state drives) for storage. In many regards they simply provide storage media as required. However, SSD are faster compared to std. HD., thus desirable but they cost more. In order to combat these high costs, the hybrid SSD was made. In basic terms its a combination of both.
Overall, the H-SSD is something of an muscled-up std. HD with a very large buffer memory. The buffer memory acts as the SSD part and the storage of long-term data resides on the std. HD section. The buffer memory pretty much the front end of H-SSD that provides fast interaction and once data needs to be stored, the std. HD becomes active. If the buffer memory becomes over-used it can fall back to the typical HD use, but that should be rare for typical users. In effect the front end of the H-SSD is doing much of the work. The buffer memory can store data but needn't be the sole source as the std. HD side allows prolonged or large storage operations. Most H-SSD will be found in laptop PCs, but will be useful in any desktop when cost isn't a concern.
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