ROM (Read-Only Memory) is a type of non-volatile storage used in computers and other electronic devices. Unlike RAM (Random Access Memory), which is temporary and loses its data when the power is turned off, ROM retains its data permanently. This type of memory is mainly used to store firmware or software that is closely tied to the hardware, such as the BIOS in a computer system. ROM is typically not writable or can be written to only a limited number of times. There are various types of ROM, including PROM, EPROM, and EEPROM, each offering different capabilities and methods for data storage and retrieval. The primary advantage of ROM is its durability and reliability in retaining data without power, making it essential for critical functions in digital devices.