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.
Dynamic RAM (DRAM) and static RAM (SRAM) chips are the working storage in every computer. DRAM is the main memory in a computer and SRAM is used for high-speed caches and buffers. Both types are byte addressable, which means that data can be read and written one byte at a time.