An SSD form factor is the size, configuration or physical arrangement of solid state storage (SSS) media. The form factor determines the media’s physical compatibility and interchangeability with other computer components or devices.
The Solid State Storage Initiative (SSSI) has identified three major form factors for the enterprise: solid state drives (SSDs), solid state cards and solid state modules (SSMs). Solid state drives come in traditional hard disk drive (HDD) form factors and will fit into the same slots. Solid state cards use standard card form factors such as Peripheral Component Interconnect Express (PCIe) and reside on a printed circuit board. Solid state modules reside in a Dual In-line Memory Module (DIMM) or small outline dual in-line memory module (SO-DIMM) and may use a standard hard disk drive interface such as Serial Advanced Technology Attachment (SATA).
A fourth form factor, the portable USB drive, is generally considered to be a consumer solid state storage.