Hybrid hard drive
(also HHD, hybrid drive, solid state hybrid drive, SSHD)
Hybrid hard drive definition
A hybrid hard drive is a computer storage device that combines elements of both traditional hard disk drives (HDDs) and solid-state drives (SSDs). A hybrid hard drive contains both spinning magnetic disks and NAND flash memory chips.
Compared to a traditional HDD, the presence of the SSD cache improves boot times, application launch times, and overall system responsiveness. However, hybrid hard drives may not match the raw speed of a dedicated SSD for all tasks — in particular, write speeds can be slower for larger files and intensive operations.
See also: solid state drive
How hybrid hard drives work
The goal of a hybrid hard drive is to provide the storage capacity of an HDD with some of the speed and responsiveness benefits of an SSD. The HDD component is used for storing data because of its lower cost per gigabyte, while the rapid SSD component is used as a cache for frequently accessed data.
To determine which data goes where, hybrid hard drives use built-in software to analyze the user’s data usage patterns. Operating system files and other frequently accessed files are stored on the faster SSD portion, while rarely accessed data (or even specific file formats typically used for long-term storage) is allocated to the HDD portion.