A RAM disk is not really a disk at all-it is memory (RAM, in the form of memory chips) that has been set aside pretending to be a disk. As long as the power is on, you can use a RAM disk just like a real disk drive-you can copy files to and from the RAM disk, display the RAM disk's directory or folder on your screen, and run any programs you've stored there. A RAM disk may be an external SCSI device that looks similar to a regular external hard disk (but is very expensive and is slowed down by the limitations of the SCSI connection), or it may be a lot of extra memory that you set aside with special RAM-disks of software, or it may be a memory card that you add to your computer.
The big advantage of a RAM disk is that because it's purely electronic (rather than a physical platter), it's much, much faster than any mechanical disk-hard, floppy, or optical. Normally, if a large application or program can't fit into regular memory all at once, the computer has to go to the hard disk from time to time and retrieve what it needs to continue working, which slows down the entire process. But if you copy the application to your RAM disk and run it from there, you'll barely notice when the program fetches more instructions from the RAM disk.
If you ever have to copy the same set of files to a bunch of floppy disks, a RAM disk will speed things up dramatically. First copy the files to the RAM disk, and from there to the floppies. On the other hand, it's not such a good idea to use a RA.Td\1isk for document files that you plan to work on and change. Remember, RAM is volatile, meaning any information that is in
RAM disappears when the power goes out or the system crashes. If you make changes in a document file parked on a RAM disk, you still must be careful to save the file to a real disk. Unless you're willing to go long periods without saving "permanently" and risk losing a lot of work, putting your documents on a RAM disk will actually slow you down.
RAM disks have another disadvantage: the memory they use is unavailable for other programs. Unless you always use the same programs, your system will run faster, on the average, if you use extra memory for a "disk cache" (see cache) instead of a RAM disk.
Recent versions of MS-DOS and Windows come with RAMDRIVE.SYS, a software device driver that will turn part of your pc's memory into a RAM disk. If you decide you want to set up a RAM disk, place the line DEVICE=RAMDRIVE.SYS in your CONFIG.SYS file (if the RAMDRIVE.SYS file is not in the root directory of your boot drive, you need to put the path name right after the equals sign).