Non­volatile random access memory (NVRAM) is any solid­state memory technology that retains its information when powered down. Usually, NVRAM does not refer to electro­mechanical storage devices such as hard disk drives. By far, the most prevalent form of NVRAM today is flash memory.

Historically, NVRAM devices have lagged behind volatile memory in terms of speed and performance. Although that gap has been closed significantly by flash, there remains plenty of room for improvement. Of most concern is the relatively slow write performance of flash (tens of microseconds) compared to DRAM (tens of nanoseconds) and SRAM (nanoseconds). Additionally, a floating gate also has an approximate number of writes it can tolerate before becoming unreliable. This phenomenon is known as write endurance and can vary between only a few thousand cycles and over a million cycles, depending on the flash technology.

There are other NVRAM technologies available besides flash, but currently they lag behind in terms of capacity and cost. Ferroelectric RAM (FeRAM) uses electric fields to orient the dipole moment of a thin film. Magnetic RAM (MRAM) stores information by controlling the electron spin that affects resistance when performing reads. Phase­change range (PRAM) uses the same technology as recordable CDs and DVDs, but PRAM reads also sense the change in resistance.