ROM - Read-only memory
What is ROM
ROM stands for Read-Only Memory. It's a type of non-volatile memory, meaning it retains data even when a device is turned off. Unlike RAM (Random Access Memory), which can be read and written to freely, ROM is designed to only be read from, not written to or altered.
Key Characteristics of ROM:
Non-volatile: Data remains even when power is lost.
Pre-programmed: Often, ROM chips are pre-loaded with data or instructions during manufacturing.
Used for firmware: Holds essential instructions for devices to operate, like firmware for initializing hardware.
Types of ROM:
PROM (Programmable ROM): Can be programmed once.
EPROM (Erasable Programmable ROM): Can be erased with UV light and reprogrammed.
EEPROM (Electrically Erasable Programmable ROM): Can be erased electronically and reprogrammed multiple times.
Where ROM is Used
ROM is commonly used in devices like computers, calculators, and game consoles to store firmware, such as the BIOS in computers, that tells the device how to start up and load its operating system.