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Random Access Memory

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What is RAM?

RAM (random-access memory) is a form of data storage that has been used in computers since the beginning of time. It serves as the main memory for computer systems, making it simple to find specific information fast. This article focuses on how RAM works, what it does, and the many types of RAM available today, such as Dynamic RAM (DRAM) and Static RAM (SRAM).

Before plunging into an explanation of what RAM is, it needs to impress on the reader’s mind the importance of having fast-access memory in a computer system. A computer is quite similar to the human brain. It computes data, stores and retrieves information as well as sends out input and output signals to various input and output devices. Now, it is of practical importance to human beings to get a computer to “remember” certain things for a longer period.


However, a computer needs someplace where it can store temporary results, program instructions, and perform interim calculations. Thus, a computer needs on hand a rough sheet of paper where it can store the in-between details of those computations it is presently working on.


To store all this information and keep it secure, a computer requires some “memory”. It requires both “long term memory” as well as “short term memory”. It needs long term memory to retain information even after the electricity is removed from it, so it acts like a memory store. And it requires short term memory so that the computer can quickly recall what instructions were given moments ago or what calculations it was performing. Preferably, the short term memory should be a fast-access memory to save time.


In this article, details of “short term memory” or RAM will be discussed.


Definition of RAM

The full form of RAM is random access memory. It is a memory device that is located on the motherboard of a computer and is used as the area of memory where the computer temporarily stores its work. RAM is volatile, which means that the contents of memory can be erased when electricity is removed from it. You can both read and write to RAM.

RAM can be likened to a slate or a whiteboard where one can write as well as read. If you want, you can erase what was written and write again.


Features of RAM

RAM memory has plenty of features that need to be perused for a thorough understanding of this subject.

  1. RAM is the internal memory of a computer. It functions as the primary memory of a computer system. Various computations can be stored here, and items from the hard drive are loaded into RAM memory for easy access by the CPU of the computer system. You can liken it to the rough paper used for doing mathematical calculations, while the hard drive is the “fair” page where the finished work is stored once the calculations are completed.

  2. RAM is volatile. Even though non-volatile versions of RAM have been developed mostly commonly, the volatile version of the RAM is used. Volatile means the memory loses the data stored on it once the electricity is turned off.

  3. This type of memory can be accessed directly without having to go through a sequence of memory locations. This random access makes RAM an expensive type of memory.

  4. RAM is the fastest type of computer memory, hence it is the memory of choice for a computer’s internal memory.

  5. The functionality and speed of the computer dramatically depend on the RAM. If there is not sufficient RAM, then a computer will not be able to load and run the operating system quickly.

Function of RAM

RAM can't store permanent data due to its volatility. A hard disk 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 filled, facts from the brain's long-term memory can be used to refresh it.

This is how a computer works as well. When RAM becomes filled, the computer's processor must repeatedly access the hard disk to replace old data in RAM with new data. The computer's performance is slowed as a result of this process.

A computer's hard disk can fill up to the point that it can't take any more data, but RAM never runs out. The combination of RAM and storage memory, on the other hand, can be entirely used up.

Speed, Capacity, & Voltage of RAM

Even among DDR4, there are significantly different types of RAM, although the basics of what RAM does are relatively simple. RAM, for example, works at different speeds, such as 2,400, 3,000, or 3,200 MHz. It also comes in various capacities, like 4, 8, and 16 GB.

To function in "dual-channel mode," current computers often require two RAM sticks (called a kit) of the same size. This simply means that a computer is running on two sticks of RAM.

Many people claim that different RAM configurations can be mixed and matched, and this is mostly true. However, maintaining a PC is much easier if the RAM has the same speed, capacity, and manufacturer, in that order of importance.

Obtaining RAM with the same voltage is also a concern, but considering that most desktop DDR4 is sold at 1.35 volts, this is less of an issue. Laptops with earlier RAM generations, on the other hand, are a different story.

If you can't find the same kind of RAM for your laptop, make sure the voltage, speed, and capacity are all the same. The quantity of RAM you can use is also limited by the capacity of your motherboard. An older laptop, for example, might only be able to use an 8 GB DDR3 memory module.

A modern desktop PC, on the other hand, may be able to use up to 128 GB of DDR4 memory, depending on its processor and chipset. However, for most people, 8 to 16 GB is sufficient.

Types of RAM

There are two types of computer RAM. They are known as Static RAM and Dynamic RAM.

Static RAM

Static RAM needs not to be refreshed continuously to retain a bit of information that is stored in it. It does not require any extra power to stop the leakage of power, so that makes it quicker than DRAM.

One SRAM memory cell is made from six CMOS transistors. But there is a drawback. SRAM requires much more chips for the same amount of memory as DRAM (since it uses six transistors). This feature makes the manufacturing cost much higher, and hence is used in high-speed cache memory.


Features of Static RAM

Static random access memory has its importance as the memory of choice for cache memory. Here are some of its features.

  • SRAM has a lower access time, around ten nanoseconds.

  • It is much faster than DRAM as the memory cells do not require to be continuously refreshed.

  • However, it consumes more power since it uses a bi-stable latch circuit, and requires a regular power source.

  • It is costly and exists on the processors between the processor and main memory.

  • It is long-lasting.

As a part of the computer RAM, SRAM is entirely necessary but expensive.

Dynamic RAM

Dynamic RAM is made from one transistor and one capacitor. Many of these tiny cells combine to form a large memory chunk. Since a capacitor is used, it needs to be refreshed from time to time to maintain the charge. Capacitors leak, hence they need to be recharged as soon as they are read, they need to be written back.


Features of Dynamic RAM

DRAM computer RAM is useful to have as a cheaper memory option. It usually serves as the main memory.

  • DRAM has a much higher access time of around 50 nanoseconds.

  • It is slower than SRAM because memory cells need to be continuously refreshed.

  • It consumes less power because the information is stored in one capacitor.

  • DRAM is less expensive than SRAM.

  • One memory cell is made up of one transistor and one capacitor so it occupies less space on the same-sized chip, providing you with more memory than an SRAM of similar size.

DRAM random access memory is the best cost-saving memory.


Read-only memory is not the same as random access memory (ROM). ROM stands for read-only memory, which is the memory that has programming permanently written on it. The contents in ROM cannot be changed, and they are kept even after the computer turns off. When the device is in use, the RAM is constantly overwritten. RAM has a higher capacity as compared to ROM. In terms of cost, ROM is cheaper than RAM.


Through this article, the reader must have received a thorough grounding in what is RAM, what are its features and the types of RAM. You should now have a better knowledge of what RAM is and why it is such a crucial part of your computer. Now, as a parent, you are ready to explain to your children why you need RAM and how the speed of the computer is affected by the size of RAM.

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FAQs on Random Access Memory

1. What is RAM in a Computer?

RAM is also known as random access memory. It is considered the internal memory of the computer. The RAM is attached to the motherboard of the computer and acts as the repository of both data, programs and the results of the programs. Every computer needs some amount of “memory”. This memory is equivalent to that part of the brain where humans store and keep the information necessary for day-to-day life.

Computers also require this functionality if they are to execute programs. Computers can both read from as well as write to the RAM. The most crucial feature of RAM is that it is a volatile memory. This volatility means that RAM does not retain in its memory the data or the information. The contents of the RAM are wiped off when the computer is shut down.

2. What are the Two Types of RAM?

Broadly, there are two types of RAM. These are Static RAM and Dynamic RAM. Static RAM can hold information in their circuitry as long as there is power applied to it. The circuitry for static RAM comprises six CMOS transistors. This type of RAM does not need to be refreshed regularly, as it does not need extra power to prevent leakages.

Dynamic RAM, on the other hand, comprises one capacitor and one transistor. Millions of these circuits are stored on a single chip to make up a DRAM. Since the circuitry of DRAM is comparatively small, the cost per unit of memory is lesser in DRAM.

3. Is RAM a Permanent Memory?

No, RAM is not a permanent memory. It loses the information stored on it as soon as the electricity is removed from it. The memory needs to be continuously refreshed if it has to “remember” anything. RAM is very expensive since it is the fastest type of memory available on the computer. Since every piece of information on the RAM can be erased, you must save the information to back it up to the hard drive. But RAM is still preferred since it is super fast and its access time is considerably lower than the access time of other memories.

4. What is RAM Used for?

RAM is like our short term memory. It is used as the working memory of the computer, where the computer can store and read the program instructions. This type of memory is volatile, so once the current source is removed, every part of the memory is wiped off, you need to back up the information on RAM if you want it to be accessible later.

RAM is generally used in the primary memory of the computer to load the data and information from the hard disk. It is also used to make cache memory, which is nothing but a fast access memory on the processor chip.

5. Does RAM make your computer faster?

Larger RAM capacity and greater memory speed result in better computer performance. RAM, on the other hand, operates with the computer's storage capacity and CPU. As a result, slow computer performance isn't always because of a lack of RAM. As a result, if your computer has an outdated chipset or requires more storage, installing more RAM may not make it faster.

6. How much RAM do you need?

The amount of RAM used is entirely dependent on the user's activities. For example, when video editing, a PC with at least 16 GB RAM is recommended, however more is preferable. To run Photoshop CC on a Mac, Adobe recommends a system with at least 3 GB of RAM for photo processing. Even 8 GB of RAM can slow things down if the user is using many applications at the same time.