Computer memory and storage - understanding the difference

in StemSocial15 days ago

While trying to describe Random Access Memory (RAM) or Hard Disk Drive (HDD), its so common to see people use the term storage instead of memory, and memory as storage. While both are components the computer uses to store and access data, there are obvious differences between the two. So in the article, I will explain:

  • how to distinguish computer memory from storage
  • the proper way to use each term

Alright without wasting time, lets look at what each term stands for.

Computer memory

When you put on your computer and start working with it, it reads data from or temporarily stores data to a component called memory. It can also be referred to as the main memory. In most computing devices, this main memory is usually the Random Access Memory (RAM). The main memory makes it easy for the computer to access data very fast, enabling it to work with various programs at a time.

The main memory does not have huge space to store data. Hence, computers still need another component that will have enough space to store both processed data and the programs that work on them. Apart from having limited space, the main memory is also volatile. This means that it does not store data permanently. It only retains data as long as the computer retains power. Once there is power outage, all data on the memory is lost and cannot be recovered - which is why a computer still needs a permanent way to retain data.

As mentioned before, the main memory of a computer provides a way to quickly access data. As such, the CPU which processes data very fast also has a device where data could be retrieved at the same speed. The bigger the size of computer main memory, the faster the computer as it enhances speed of data access during program execution.


From the above explanations, we can see some main characteristics of computer main memory. They are as follows:

  • It facilitates quick and direct data access from programs
  • It losses data once there is loss of power (volatile)
  • It cannot hold large amount of data
  • Ramdom Access memory (RAM) is the computer main memory

Having seen meaning and characteristics of memory, it will be easy to understand computer storage. Lets get into that quickly.

Computer Storage

Computer storage is the secondary way means of storing and retrieving data. The storage is a piece of hardware with large space where the computer can store data permanently. When there is power outage, all data stored in the storage is retained and not lost. In most basic computers, the storage component is usually the Hard disk drive (HDD). Most recently, there is also Solid State Drives (SDD) that are also considered computer storage.

The storage is different in the way it provides access to data. It is inherently slow, which is why it was not designed to provide quick data access - hence the RAM. The computer storage is usually considered as backup store of data for the computer. Hence, it usually has a large space for data storage. There are sizes from 100 Gigabyte to 1 Terabyte and more. This ensures that the computer will not lack space for both installation of programs and saving of processed data.


From the above explanations, here is what we can deduce about computer storage:

  • It holds large data because it usually has large capacity
  • As regards data access, it is slower than the main memory
  • It does not loose data saved in it when the computer looses its power
  • Hard Disk Drive (HDD) or Solid State Drive (SDD) are the computer storage

The right way to use the terms

Both memory and storage provides a way for the computer to store and retrieve data. But we have seen that each has a different way of doing this job and different hardware too. For example, the HDD cannot replace the RAM and vice-versa. Each of these components must be present in a computer for it to function well.

So when referring to the RAM, its more appropriate to use the term memory. The HDD or SDD can both correctly be termed as storage.

In keeping with the above explanations, the following statements are best understood as the correct terms are used:

  • Your computer is probably running slow because the memory (RAM size) is small.
  • How much data can your computer store (what's the size of its HDD or SDD)?



Not have enough space in your hard drive or system be it mobile phone is a stress to the phone not to talk if the operator. Whenever the system memory is full, the system slowed down it's speed of operation thereby making the work boring. Thanks for this update.

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