The oral mucosa in the area of crenation is usually of normal color, but there may be erythema (redness) if exposed to a high degree of friction or pressure. Crenated tongue is usually asymptomatic and harmless.
ROM stands for read-only memory. It's used to store the start-up instructions for a computer, also known as the firmware. Most modern computers use flash-based ROM. It is part of the BIOS chip, which is located on the motherboard.
RAM = Random Access Memory. That's the volatile high speed memory that is used inside a computer that lets you store internal applications and data. Everything written to RAM is lost when you turn off the computer, so usually, important data is written to a long-term storage device, such as a disk or Flash Memory. CPU = Central Processing Unit.