Solid-state hybrid drive

A solid-state hybrid drive (SSHD), or simply hybrid drive, is a storage device that combines the speed benefits of a solid-state drive (SSD) with the more cost-effective mass storage space of a hard drive.

Adoption by Apple
In 2012, Apple introduced a their propietary implementation of hybrid drive in the form of a Fusion Drive as an option in the Intel-based iMac. This option was discontinued from the 27-inch iMac with Retina display in 2020. Fusion Drives were also offered in the Mac mini from 2012 to 2018.

Users of older MacBooks and MacBook Pros can swap their internal hard drive for a 3rd-party hybrid drive to gain the speed benefits, limited only by the bandwidth of the SATA connector. However, more recent notebook models from Apple have switched to faster SSD storage without the physical space to accommodate a hybrid drive. With the dropping prices of storage devices, SSDs have become a more appealing option than SSHDs.