ROM is an IC that has the ability in one reading, but it cannot (easily) be written to. ROM also can be called Permanent Memory. It doesn't need Electromotive force because it has a class of storage media used in computers by itself

1. ROM :Read Only Memory Memory is a class of storage media used in computers. it can(easily) be read only.
2. PROM : Programmable Read Only Memory is a class of storage media used in computers. it can(easily) be read only.
3. EPROM : Erasable Programmable Read Only Memory is memory unit that is developed stead of ROM, allow users to install programs or write data by themselves, but PROM can only be programmed once.
4. EEPROM : Electrical EPROM is memory unit that has more ability than PROM. It can be erased by exposure to ultraviolet light then rewritten via an EPROM programmer. However, when finish recording, it should typically be covered by a label to prevent accidental erasure..
5. FEPROM : Flash EPROM EPROM is Read Only Memory that has quality like EPROM; simply, it can be written and erased data what you don't want. Differently, EEPROM is electrically erased stead of using ultraviolet.
6. ROM BIOS : ROM Basic Input / Output System is Read Only Memory that has quality like EEPROM, allow the entire ROM to be erased and written by using electric. Differently, FEPROM has more speciality, it is Flash Erasable Programmable Read-Only Memory that can be erased and written more quickly. is ROM chip that contain fundamental programs for controlling and communicating with other devices in order to have correctly work. ROM BIOS will always be available and will not be damaged by disk failures. It also makes it possible for a computer to boot itself and give preparation for RAM. Next, ROM BIOS will read softwares from CD, and then allow operating system working according to users. Moreover, ROM BIOS also has importance; it can handle fundamental devices. Although ROM BIOS has several types, they have the same work