A solid-state drive (SSD) is a nonvolatile storage device that stores persistent data on solid-state flash memory. Solid-state drives actually aren’t hard drives in the traditional sense of the term, as there are no moving parts involved.
A traditional hard disk drive (HDD) consists of a spinning disk with a read/write head on a mechanical arm called an actuator. An SSD, on the other hand, has an array of semiconductor memory organized as a disk drive, using integrated circuits (ICs) rather than magnetic or optical storage media.
An SSD may also be referred to as a solid-state disk.
Development and adoption of SSDs has been driven by a rapidly expanding need for higher input/output (I/O) performance. SSDs have much lower random access and read access latency than HDDs, making them ideal for both heavy read and random workloads.
High-performance servers, laptops, desktops or any application that needs to deliver information in real-time or near real-time can benefit from solid-state drive technology.
Those characteristics make enterprise SSDs suitable to offload reads from transaction-heavy databases, to alleviate boot storms with virtual desktop infrastructure, or inside a storage array to stage hot data locally for off-site storage in a hybrid cloud scenario.
SSD form factors
The Solid State Storage Initiative has identified three major SSD form factors for the enterprise:
- SSDs that come in traditional HDD form factors and fit into the same slots.
- Solid-state cards that use standard card form factors, such as Peripheral Component Interconnect Express (PCIe), and reside on a printed circuit board.
- Solid-state modules that reside in a Dual In-line Memory Module (DIMM) or small outline dual in-line memory module (SO-DIMM), and may use a standard HDD interface such as Serial Advanced Technology Attachment (SATA).