RAM disk

1. Also known as a RAM drive, a RAM disk is a software-generated disk drive that stores information in the computer memory instead of on a physical disk drive. Because information is stored and accessed directly from the computer memory, RAM disk drives are faster; however, they are much more expensive than a standard hard disk drive.
2. RamDisk is also a software product by SuperSpeed that enables Microsoft Windows computers to increase the overall performance of the computer by creating a virtual drive in memory.

Also see: Hard disk drive definitions, Memory definitions