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Abhay Prajapati
Abhay Prajapati

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What are🤯 Main Memory, Stack, RAM, ROM, secondary Memory SSD and else? complete answer

Memory and Storage in electronics

Electronics have two main types of memory Main and secondary.

The primary use of Main(Primary) Memory

is to store the data of task👨🏾‍🏭 that is working currently, as Main memory is very close to CPU(Processor) 🖥, to CPU can talk to Main memory very easily, this could be anything the tab us are currently open, webpage, cursor, the variable that you have written these all are stored in RAM,

but even you when you close you know when you close the tab, or programme if you haven't save📁 that data, it will be lost❌.

so this should be saved somewhere else, and when you open the tab again, it will be there, here Storage, comes into play you can store your data in any device, Floppy💾, Hard Disk Drive💽, SSD🖴 and USB🔌, also it can be on Cloud☁️, it totally depends on you the user.

Use of Secondary Memory

SSD Image
as talked above Secondary have of a different type but the function is the same as store permanently✅.
from operating system🐧, application📱, and other files📂.

Main memory

It offers a very fast read/write speed but less storage capacity, it requires a power supply and as power goes it losses it's data.

  1. RAM
  2. ROM
  3. Cache(cash)

are in the Main memory.


RAM Stick
any thing runs has to loads on the RAM as CPU can process that fast, and also any location(data) can be access by CPU in no time(instantly), so it is called as Random Access Memory, it is read/write speed.

the code you write; and when you run it; it runs here, Stack the famous word in CS which I don't understand at the beginning, makes its house inside the RAM.


Rom is directly writing for you from the manufacturer, it is read-only, so it is called Read-Only Memory
the basic function is to start the applications' control of the Input/Output devices, and also to start the OS.

As, you don't need to config this stuff they are read-only, which means you and your computer can read from those files.


it stores the command👆🏾 that are frequently told to the processor(CPU), so it is called Cache Memory. It is quickest to access with the least storage capacity

Secondary Storage (Memory)

it offers read/write speed and storage capacity, but it is not fast to access as compared to Main memory(RAM), not dependent on the power you can access you even if the power goes,1000X or times. think na you have to turn your computer off📴 does it losses it's operating system🐧 memory, you saved files📂, and you can access them again, also you can 🚌 from one device to another, and access there

There are two types of Secondary memory, Optical Dics💿, Floppy Disk💾, SSD🖴, HDD(hard disk drives)💽.

And these are the storage devices great storage capacity, it has multiple faces

these are all I knew about memory and storage, and that i wanted to share, if you want to learn memory I would recommend you to read the article from @Issac_Computer_Science

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Thank you.

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Abhay Prajapati

Want to learn more about Memory and Storage checkout this article from Issac Computer science

Timeless DEV post...

Git Concepts I Wish I Knew Years Ago

The most used technology by developers is not Javascript.

It's not Python or HTML.

It hardly even gets mentioned in interviews or listed as a pre-requisite for jobs.

I'm talking about Git and version control of course.

One does not simply learn git