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.
The BIOS is special software that interfaces the major hardware components of your computer with the operating system. It is usually stored on a Flash memory chip on the motherboard, but sometimes the chip is another type of ROM. When you turn on your computer, the BIOS does several things. This is its usual sequence: 1.