NVRAM

Non-Volatile RAM. A type of RAM, which typically uses SRAM with a battery backup to make it non-volatile, or using SRAM with an EEPROM as backup storage for when there is no power. Most computers store things like BIOS settings in this.

Also used in many high-performance NFS servers to improve throughput. NFS suffers from the small write problem, and using NVRAM as an intermediate write-through cache can improve performance. NVRAM is expensive, though...