Abstract
Hybrid hard disk drives combine a magnetic hard disk drive and flash memory into a single device. Here, the high density of magnetic hard disk drive and low power, high reliability and high speed of flash memory technology come together. In a hybrid hard disk drive, non- volatile cache is used to store frequently accessed sectors and critical system data. Those portions of operating systems required during booting are stored in flash memory, thus speeding up booting process. Most of the time disk spindle is kept idle, thus saving power. NAND flash memory is incorporated in a hybrid hard disk using NAND design options such as the use of embedded flash disk. Hybrid hard disks have several benefits such as hard disk power consumption is reduced by about 70-90%, faster boot and resume from hibernation. They are more rugged and shock resistant. Hybrid hard disk drives are expected to be available in market