Difference Between RAM and ROM, Comparisons Explained

RAM and ROM are the two important parts of a laptop and desktop. Your computer’s RAM is essentially its brain. It’s on par with your processor and hard disc in terms of importance. The performance of your computer and its ability to support various types of applications are maximized when you have the proper quantity of RAM installed. And ROM is a type of electronic storage that comes built into a device during manufacturing.

Difference Between RAM and ROM (RAM vs ROM)

Often people get confused between RAM and ROM. Some of them even think they are the same. But no, is completely different from each other. Keep on reading and you will get to know the real difference between the two. So let’s get started.

What Is RAM?

RAM stands for Random Access Memory. It is the hardware in a computer and laptop that stores the operating system (OS), application programs, and data in use so that the CPU may access them rapidly. A computer’s main memory is known as RAM. Other types of storage, such as a hard disc drive (HDD), solid-state drive (SSD), or optical drive, are substantially slower to read from and write to.

Random Access Memory (RAM) is a volatile storage medium. This indicates that data is stored in RAM while the computer is turned on, but it is lost when the computer is turned off. The OS and other files are reloaded into RAM when the machine is restarted, usually from an HDD or SSD.

What Is The Function Of RAM?

RAM can’t store persistent data due to its volatility. A hard disc drive can be compared to a person’s long-term memory, while RAM can be compared to a person’s short-term memory. Short-term memory is focused on the task at hand, but it can only hold a certain number of things in mind at any given time. When a person’s short-term memory is full, facts from the brain’s long-term memory can be used to refresh it.

This is how a computer operates as well. When RAM becomes full, the computer’s processor must repeatedly access the hard disc to replace old data in RAM with new data. The computer’s performance is slowed as a result of this process. You have to increase the RAM in Windows for smooth work.

Type Of RAM

There are two types of RAM:

  • Dynamic Random Access Memory (DRAM) makes up the typical computing device’s RAM, and as was previously noted, it needs that power to be on to retain stored data.
  • Static Random Access Memory (SRAM) also needs constant power to hold on to data, but it doesn’t need to be continually refreshed the way DRAM does.

What Is ROM?

ROM, which stands for read-only memory, is a memory device or storage medium that stores information permanently. It is also the primary memory unit of a computer along with the random access memory (RAM). It is called read-only memory as we can only read the programs and data stored on it but cannot write on it. It is restricted to reading words that are permanently stored within the unit.

The manufacturer of ROM fills the programs into the ROM at the time of manufacturing the ROM. After this, the content of the ROM can’t be altered, which means you can’t reprogram, rewrite, or erase its content later. However, there are some types of ROM where you can modify the data.

What Is the Function Of ROM?

ROM performs a very large function in running our computer and laptop. The important function of ROM in the computer is that as soon as the computer is started, the ROM gives the instruction to load the boot loader program into RAM.

As soon as the instruction is received, the operating system is loaded into the RAM and the computer system is started.

The ROM memory chip already stores instruction data about which functions to execute and when. ROM knows which device is connected to the computer and which device is not. For example – keyboard, mouse, printer, scanner and operate the computer fan, etc.

Types Of ROM

  • MROM (Masked ROM)– The very first ROMs were hard-wired devices that contained a pre-programmed set of data or instructions. These kinds of ROMs are known as masked ROMs, which are inexpensive.
  • PROM (Programmable Read-Only Memory)– PROM is read-only memory that can be modified only once by a user. The user buys a blank PROM and enters the desired contents using a PROM program. Inside the PROM chip, there are small fuses that are burnt open during programming. It can be programmed only once and is not erasable.
  • EPROM (Erasable and Programmable Read-Only Memory)– EPROM can be erased by exposing it to ultra-violet light for a duration of up to 40 minutes. Usually, an EPROM eraser achieves this function. During programming, an electrical charge is trapped in an insulated gate region. The charge is retained for more than 10 years because the charge has no leakage path. For erasing this charge, ultra-violet light is passed through a quartz crystal window (lid). This exposure to ultra-violet light dissipates the charge. During normal use, the quartz lid is sealed with a sticker.
  • EEPROM (Electrically Erasable and Programmable Read-Only Memory)– EEPROM is programmed and erased electrically. It can be erased and reprogrammed about ten thousand times. Both erasing and programming take about 4 to 10 ms (millisecond). In EEPROM, any location can be selectively erased and programmed. EEPROMs can be erased one byte at a time, rather than erasing the entire chip. Hence, the process of reprogramming is flexible but slow.

Key Difference Between RAM and ROM

Point Of Difference



Data retention

RAM is a volatile memory which could store the data as long as the power is supplied.

ROM is a non-volatile memory which could retain the data even when power is turned off.

Working type

Data stored in RAM can be retrieved and altered.

Data stored in ROM can only be read.


Used to store the data that has to be currently processed by CPU temporarily.

It stores the instructions required during bootstrap of the computer.

CPU Interaction

The CPU can access the data stored on it.

The CPU can not access the data stored on it unless the data is stored in RAM.


It is a high-speed memory.

It is much slower than the RAM.

Size and Capacity

Large size with higher capacity.

Small size with less capacity.

Used as/in

CPU Cache, Primary memory.

Firmware, Micro-controllers


The data stored is easily accessible

The data stored is not as easily accessible as in RAM



Cheaper than RAM.

Conclusion On The Difference Between RAM and ROM

The difference between RAM (Random Access Memory) and ROM (Read Only Memory) is RAM is volatile. So, its contents are lost when the device is powered off. Whereas ROM stores all the applications that are needed to boot the computer initially, it only allows for reading.

I hope, now you have a clear concept between RAM and ROM. If you still have any questions and confusion, let us know in the comment section below. We will be happy to respond ASAP.

Techyuga Team

Techyuga Team

Hello World, We are a team of repair experts for laptops, mobile phones, iPhones, and more. We write a lot of how-to guides, repair tips, and more on our site, and help millions across the world. Do follow us on Social media for more..

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