Solid-State Drive

A solid-state drive, or SSD, is a data storage device that uses integrated circuits to store data persistently rather than the spinning magnetic platters of a hard disk drive or the tape of a tape drive, and is also called a solid-state disk or solid-state device. Storage Technology Corporation built an early solid-state drive using volatile DRAM in 1978, with an initial capacity of 45 megabytes, well before flash-based storage existed. SanDisk introduced the first flash-memory-based solid-state drives in 1991, starting at a 20 megabyte capacity in a 2.5-inch form factor, and since 2009 most SSDs have used non-volatile NAND flash memory rather than DRAM, the shift that made SSDs practical for everyday consumer and enterprise use.