Many types of memory exist in computers, which store information anywhere from a few milliseconds to a year or longer. Electronically erasable programmable read-only memory (EEPROM) acts as a special type of memory that stores information indefinitely.
Read-only memory (ROM) cannot be written (or changed), but allows a computer to read and interpret data from it. Random access memory (RAM) allows a computer to both read and write data. Together, RAM and ROM make up two major types of memory.
Purpose of ROM
Because read-only memory can only be read and not altered, it is also known as "non-volatile storage." ROM acts as a security measure by providing indefinitely stored data that cannot be changed by accidental or malicious events.
Due to the secure state of ROM, basic input and output settings (BIOS) store it on your motherboard and use it to boot your computer. EEPROM acts as a form of memory that retains most of the security benefits of ROM, while allowing it to be reprogrammed in the future with special software.