What is-ROM Read Only Memory

CPU can only read from Read Only Memory but cannot write to its location. Read only memories are also random access in nature, which means The CPU can randomly access any location within ROM also. The unit of storage for a memory location is usually either a byte which means eight bits. Improvement in technology for constructing flexible ROM has brought, PROM, EPROM, and EEPROM into existence. PROM(Programmable read only memory), EPROM(erasable programmable read only memory), EEPROM(Electrically erasable Programmable read only memory.) Primary memory made up with RAM is volatile in nature, the contents of RAM are lost when the power to it gets removed. The contents of ROM are not lost even though power may not be available to it.