What is RAM and ROM – Easy Guide for Beginners

Published: 3 Sep 2025

Do you know how a computer knows what to do or how it remembers your work? It happens because of two important parts that are called RAM and ROM. These are the types of Primary memory.

Memory is the most important part of the computer, responsible for storing data and information permanently and temporarily.

In this article, we’ll learn about RAM and ROM.

Table of Content

RAM
1. How RAM Works?
ROM
1. How ROM Works?
Role of RAM and ROM in Daily Computer Use
Common Myths About RAM and ROM
Conclusion
FAQs

RAM

RAM stands for Random Access Memory. It is the short-term memory of a computer or laptop. RAM stores data temporarily while you’re using the device, so the computer can work faster.

Think of RAM like a study table. The more space (RAM) you have on your tablet, the more books (apps or files) you can open and work with at the same time.

How RAM Works?

When you turn on your computer and open apps like Chrome, Word, or a game, your computer loads those apps into RAM from the hard drive.

RAM helps your computer quickly read and write data that it needs right now. It does not store data forever; when you shut down or restart, RAM gets cleared.

So, more RAM = faster performance and better multitasking.

Example

Let’s say you open a browser, a game, and music at the same time:

All three apps are loaded into RAM.
Your computer uses RAM to keep these apps running smoothly.
If RAM is full, your computer may slow down or freeze.

Just like having too many books open on a small desk, if there’s not enough RAM, your computer struggles to handle everything.

ROM

ROM stands for Read-Only Memory. It is a permanent memory in a computer. Unlike RAM, the data in ROM does not get erased when the computer is turned off. ROM holds important instructions that help the computer start up properly.

You can only read the data in ROM; you cannot change or delete it easily.

How ROM Works?

When you turn on your computer, the ROM gives the system basic instructions like:

Checking all parts (keyboard, screen, memory)
Starting the operating system (like Windows)
Making sure everything is ready to use

These instructions are written by the computer maker and stay there forever.

ROM works even without electricity because it is non-volatile memory. That means it keeps its data even when the power is off.

Example

When you press the power button on your computer or laptop:

ROM runs a program called BIOS or UEFI
This program checks if your hardware is okay
Then it helps load the operating system from the hard drive into RAM

So, without ROM, your computer wouldn’t even know how to turn on properly.

Role of RAM and ROM in Daily Computer Use

Computers need both RAM and ROM to work properly. These two types of memory do different jobs, but both are important for your computer to run smoothly every day.

RAM handles temporary data for quick access, while ROM stores essential instructions permanently.

How Do They Help Run Your Computer?

RAM (Random Access Memory) helps your computer do tasks quickly. It stores the data of apps and files you are using right now.
ROM (Read-Only Memory) stores permanent startup instructions that tell your computer how to turn on and get ready for use.

Think of it like this.

RAM is like a whiteboard where you write and erase things as you work.
ROM is like a printed instruction manual that never changes and helps start everything correctly.

What Happens If RAM Is Low?

If your computer has low RAM, here’s what you might notice:

Apps take longer to open
Switching between tabs or programs feels slow
The computer may freeze or hang
Sometimes apps even crash or close suddenly

This is because RAM is too full and doesn’t have enough space to keep everything running smoothly. It’s like trying to work on a tiny desk with too many books on it.

Tip: Adding more RAM can make your computer faster and better at multitasking.

Why is ROM Always Needed?

ROM is essential because.

It gives your computer the basic instructions to start up.
Without ROM, your computer won’t know what to do when you press the power button.
ROM stays safe and unchanged even if your power goes out or your computer restarts.

Even though you don’t see ROM working, it’s always doing its job in the background, making sure everything starts correctly every single time.

Common Myths About RAM and ROM

Many people get confused between RAM and ROM, especially when they’re new to computers. Let’s clear up some common myths and explain the truth in simple words.

More ROM

Truth: ROM has nothing to do with speed.

ROM is only used when your computer starts up. It holds startup instructions and is not involved when you open apps or do your daily work.

Think of ROM as a starter switch. It helps your computer turn on, but it doesn’t make it run faster.

RAM saves data

Truth: RAM is temporary memory.

RAM only holds data while your computer is on. As soon as you shut down or restart, everything in RAM is gone.

RAM is like a whiteboard; you write things while you work, but when you’re done, it gets erased.

ROM if you have enough RAM

Truth: You always need ROM, no matter how much RAM you have.

RAM and ROM do different jobs.

ROM is needed to start the computer.
RAM is needed to run programs smoothly after they start.

It’s like saying you don’t need a key (ROM) to start a car if you already have fuel (RAM). Both are needed.

Conclusion

In this article, we’ve learned about the difference between RAM and ROM. RAM and ROM are two different types of memory in a computer, but they have different and specific tasks.

RAM loses data, and ROM stores data permanently. RAM is more flexible, but it is more costly; ROM is more stable and secure.

You can use a computer better and manage files well when you know the difference between RAM and ROM.

I hope you found this information helpful. Let me know your thoughts in the comment section below!

FAQs

Still curious? Read the FAQs below to find quick and helpful answers!

What is the main difference between RAM and ROM?

RAM is a temporary memory that stores data only while the computer is on. The main difference is that RAM is volatile (data is lost when power is off), while ROM is non-volatile (data stays even when power is off).

Can we change data in RAM?

Yes, we can change data in RAM. RAM is designed to read and write data quickly, so the computer can update it anytime while it’s running. However, all data in RAM is lost when the computer is turned off.

What happens when RAM is full?

When RAM is full, your computer slows down because it doesn’t have enough space to handle more tasks. Apps may freeze, lag, or crash, and switching between programs becomes difficult.

Does RAM store files permanently?

No, RAM does not store files permanently. It only holds data temporarily while the computer is on. When you shut down or restart, all the data in RAM is erased automatically. That’s why you must save your work on the hard drive before turning off your computer.

Is ROM bigger than RAM?

Usually, RAM is bigger than ROM in modern computers. RAM needs to be large because it handles many apps and tasks at the same time. ROM is smaller because it only stores startup instructions, which don’t take much space.

Can I upgrade RAM and ROM?

You can upgrade RAM on most computers to make them faster and better at multitasking. However, ROM cannot usually be upgraded, because it is built into the motherboard and holds permanent startup instructions. So, while RAM is flexible, ROM is fixed in most cases.

Is ROM also a type of memory?

Yes, ROM is a type of memory used in computers and other devices. It stores permanent instructions that help the system start up. Unlike RAM, ROM keeps its data even when the power is turned off.

Does RAM save data when the power goes off?

No, RAM does not save data when the power goes off. It is a volatile memory, which means all the data stored in it is erased as soon as the computer is turned off or restarted. That’s why it’s important to save your work regularly.

What happens if a computer has low RAM?

If a computer has low RAM, it may become slow and unresponsive when running multiple programs. Apps can take longer to open, and the system might freeze or crash during use. Low RAM also makes it hard to multitask smoothly, affecting overall performance.

Do all devices have RAM and ROM?

Yes, all digital devices like computers, laptops, smartphones, and tablets have both RAM and ROM. RAM helps the device run apps and tasks quickly, while ROM stores the startup instructions needed to turn the device on. Both are essential for the device to work properly.