Question

what kind of instructions are stored in ROM

Answer 1

It contains the basic instructions for what needs to happen when a computer is powered on. This is typically referred to as the firmware of a computer. The firmware represents the basic code to get the computer started. Once the computer is up and running, the CPU takes over. Firmware is also referred to as BIOS, or basic input/output system. On most modern computers, the read-only memory is located on a BIOS chip, shown on the left. The BIOS chip is normally plugged into the motherboard.

You have probably heard of the term CD-ROM, which stands for compact disc read-only memory. This is another type of ROM that is impossible or difficult to change; however, the term ROM by itself is used to indicate the memory that stores the firmware for a computer.