Read Only Memory (ROM)

What is Read Only Memory (ROM)?

The Read-Only Memory (ROM) is part of the main memory that holds manufacturers’ instructions, which assists the Central Processor in performing special operations.

These operations include telling the CPU what to do when the power is turned on, checking to see that the cables to the printer and the monitor are well connected, and interpreting the meaning of each key on the keyboard.

It is a non-volatile memory that stores information permanently, even when the power is turned off.

Unlike the RAM, the instructions on the ROM do not disappear when the power is turned off. Information on the ROM can only be read. A good example of the ROM program is MS-DOS. ROM has the capacity to retain data and programs forever even during a power failure. ROM stores BIOs. It is smaller than RAM. Its content and information do not change.

Types of ROM:

The various types of ROM include:

1. PROM: Programmable Read-Only Memory (This version cannot be changed)

2. EPROM: Erasable Programmable Read-Only Memory (This version can be erased)

3. EEPROM: Electronically Erasable Programmable Read-Only Memory (This version can be erased by the application of current over time.

Characteristics of ROM:

Below are key characteristics of ROM:

Non-Volatility: ROM is non-volatile memory, in contrast to RAM. Data is kept even when there is no constant power source. This quality makes it useful for storing crucial information and instructions that must be kept.

Stability: ROM serves as a reliable and trusted storage medium as its contents cannot be readily changed or altered.

Read-Only Access: ROM is a type of memory that only enables data to be read from it, as the name suggests. The machine or user cannot alter or replace the stored information.

Storage Capacity: When compared to RAM, ROM typically has a reduced storage capacity. It is often expressed in megabytes (MB).