Read-Only Memory (ROM) is storage technology that permanently stores data in a chip built into computers and other electronic devices. ROM includes the most basic programming needed to start a computer, often referred to as Basic Input/Output System (BIOS). Your BIOS holds the program and software instructions to boot up your computer.
Because ROM is read-only, it is not easily changed. To update ROM you need to perform a “Flash” of the ROM which means it is critical that power not be interrupted or else the computer in which the ROM sits may no longer function at all. Once Flashed, ROM is permanent and non-volatile, meaning it also holds its memory even when the power source is removed. By contrast, random access memory (RAM) is volatile; losing data when a power source is removed.
What are some Advantages and Disadvantages of ROM?
- It’s non-volatile and cheaper than RAM
- They are static, meaning they do not need refreshing every time it’s used
- Circuits are simple making ROM more reliable than RAM
- Data can be stored permanently
- It helps to start the computer and loads the operating system (OS)
- ROM is typically read-only so changes involve a convoluted process of “Flashing” the ROM chip with a new instruction set.