Read-Only Memory (ROM)

Read-Only Memory (ROM)

Rom stands for Read Only Memory. The instructions in ROM prepare the computer for use. These contents of ROM can only be read but cannot be changed or deleted. It is not possible to write new information or instruction in ROM. It stored data and instructions permanently. When the power is switched off, the instructions stored in ROM are not lost. That is why ROM is known as non-volatile memory.The data and programs in ROM are stored by the manufacturer. ROM is used to store frequently used data and instructions. The instructions in ROM are automatically loaded into the memory of computer when the computer is switched on.

Types of ROM
Different types of ROM are as follows:

1. PROM:

PROM stands for Programmable Read Only Memory. This form of ROM is blank. The user or manufacturer can write data and programs on it using special devices. The user can write data and instructions, the error cannot be removed from PROM. The chip becomes unusable.

2. EPROM:                                                           
 EPROM stands for Programmable Read Only Memory. This from of ROM is initially blank. The user or manufacturer can write data and programs on it using special devices. The data and programs written on it can be erased using ultraviolet rays. The user then can write new program on it.

                                                                           

3. EEPROM:
EEPROM stands for Electronically Erasable Programmable Read Only Memory.The user can erase and write instructions in EEPROM using electrical devices.The user can erase its contents electronically if any error occurs in writing instructions.The contents of EEPROM.