ROM - Read Only Memory is a chip with instructions that cannot change. The ROM contains the BIOS on your home computer. This tells the computer how to start up when you switch it on. This means that ROM is non-volatile as it retains the information once the power is off.
Example 1: Due to its permanent data storage nature, ROM is used in different types of embedded systems. An example of an embedded system would be your washing machine, sat nav, etc as these contain instructions and data that do not need to be changed.
Example 2: Embedded systems that use ROM are found in things such as TVs, microwaves, refrigerators, washing machines, calculators, printers, plotters, FAX machines, electronic toys, automatic doors, and many many more. See Embedded Systems for more information.
Example 3: When you switch on your PC at home, it starts up, loads Windows, and ensures your keyboard, mouse, and monitor are working. This happens because the ROM has set all this in motion, it knows the hard drive, how much RAM you have, the fact a keyboard is connected, the operating system, and much more. It uses this information to make sure your computer starts correctly.
Example 4: If you were to unplug your keyboard and then switch your computer on, it would beep to say there was no keyboard.
