Glossary 187
RAC — Remote access controller.
RAID — Redundant array of independent disks. A method of providing data
redundancy. Some common implementations of RAID include RAID 0, RAID 1,
RAID5, RAID 10, and RAID 50. See also guarding, mirroring, and striping.
RAM — Random-access memory. The system’s primary temporary storage area for
program instructions and data. Any information stored in RAM is lost when you turn
off your system.
RAS — Remote Access Service. This service allows users running the Windows
operating system to remotely access a network from their system using a modem.
readme file — A text file, usually shipped with software or hardware, that contains
information supplementing or updating the product’s documentation.
read-only file — A read-only file is one that you are prohibited from editing or
deleting.
ROM — Read-only memory. Your system contains some programs essential to its
operation in ROM code. A ROM chip retains its contents even after you turn off your
system. Examples of code in ROM include the program that initiates your system’s
boot routine and the POST.
ROMB — RAID on motherboard.
rpm — Revolutions per minute.
RTC — Real-time clock.
SAS — Serial-attached SCSI.
SATA — Serial Advanced Technology Attachment. A standard interface between the
system board and storage devices.
SCSI — Small computer system interface. An I/O bus interface with faster data
transmission rates than standard ports.
SDRAM — Synchronous dynamic random-access memory.
sec — Second(s).