What Is RAM?

Date First Published: 29th June 2022

Topic: Computer Systems

Subtopic: Computer Hardware

Article Type: Computer Terms & Definitions

Difficulty Level: 4/10

Learn more about what RAM is in this article.

Stands for random access memory. RAM is a form of volatile memory used to temporarily store data the processor is currently using so that it can be quickly reached. For example, when opening a word processor, the computer will copy that information to the RAM. When an existing document is loaded, that information is also copied to the RAM. If it is saved, the data will get copied to the hard drive. However, if the computer turns off and the document is unsaved, all of that work is gone because RAM is a form of temporary storage. Also, when a program is closed, it will be taken out of the RAM so that the space is free for the computer to work on the next thing.

RAM can be thought of as an office desk. An office desk allows quick access to office equipment, such as pens, pencils, and other items needed now. Without a desk, everything would be stored in drawers and cupboards, greatly increasing the amount of time required to complete everyday tasks as people would have to constantly open these drawers or cupboards to get what they need and also spend extra time putting the items away. In a similar way, all the data that is actively being used on a computer is temporarily stored in the RAM.

Note:

RAM is sometimes referred to as the ‘memory’, even though there are other types of memory available in a computer and it is completely unrelated to the amount of file storage a hard drive has.

RAM is much faster than a hard disk that has physical limitations, such as rotation speed. In fact, it is 20-100 times faster, depending on the type of hardware. For example, programs may take much longer to load when a computer is first booted. However, when they are closed and relaunched, the program opens much faster. This is because the program is loaded out of the much faster RAM rather than the hard drive.

Every digital device has RAM, including desktop computers, laptops, tablets, mobile phones, and IoT digital devices. It is not possible to run a computer without RAM as every computer system needs RAM to send instructions to the CPU.

Note:

Since the RAM is a form of volatile memory, the temporary storage goes away when the computer is turned off. It is much different from hard disk drives, ROMs, and solid-state drives, which use non-volatile memory. For example, when saving a document to a hard drive, it does not get removed when the computer is turned on.

RAM Capacity

RAM capacity usually comes in three options, which include 2GB, 4GB, 16GB, or additional RAM. Obviously, the more RAM, the faster the processing speed when using multiple programs, browsing tabs, and performing computing-intensive tasks, such as gaming and video editing. However, it is also more expensive. Therefore, it is only recommended to buy what you need. In most cases, users need much less RAM than hard disk space.

When a computer runs out of RAM, the operating system will start to work less efficiently, slow down, and use the hard drive space as ‘virtual memory’ to compensate for the insufficient amount of RAM.

Types Of RAM

• DRAM (Dynamic Random Access Memory) - Where each bit of data is stored on a separate capacitor. Since it is dynamic, it needs to be refreshed or given a new electronic charge every few milliseconds in order for the memory to keep holding its data.
• SRAM (Static Random Access Memory) - Where data is stored using a static method and remains constant as long as electric power is supplied to the memory chip. The amount of power consumed varies depending on how often the memory is accessed.
• SDRAM (Synchronous Dynamic Random Access Memory) - An extension to DRAM that that synchronises itself with the system clock of the computer. This increases the number of instructions that the processor can perform in a given period of time.

Difference Between ROM and RAM

The terms ‘ROM’ and ‘RAM’ look similar, but they are two completely different types of memory. Read-Only Memory (ROM) is a form of memory that the computer can read but not write to, as suggested in the name. An example of ROM is a cartridge used in video game consoles.

RAM Limitations

Computers have limitations in terms of the amount of RAM that can be installed. For example, it is necessary to use a 64-bit version of Windows to install more than 4 GB of RAM. 64-bit operating systems support up to 128 GB, although it is not always necessary to buy extremely high amounts of RAM. Having only 2 GB of RAM when using a newer operating system, such as Windows 10 will cause a slow computer with ‘low memory’ warnings.

History

The first form of RAM was the Williams tube. It came about in 1947 and stored data as electrically charged spots on the face of a cathode-ray tube. Memory was known as random access because the electron beam of the cathode-ray tube could read and write the spots on the tube in any order.

The capacity of the Williams tube ranged from a few hundred to around a thousand bits. It was developed at the University of Manchester in England and provided the medium that the first electronically stored program was implemented in the Manchester Baby computer. It successfully ran a program on 21st June 1948.

In 1947, magnetic-core memory was introduced. It was developed up until the mid-1970s and became a widely used form of RAM. It relied on an array of magnetised rings. It was possible for data to be stored with one bit stored per ring by changing the sense of magnetisation for each ring.

Because each ring had a combination of address wires to select and read or write it, access to any memory location in any sequence was possible. The standard form of computer memory was magnetic-core memory until it was replaced by solid-state metal-oxide-silicon in integrated circuits during the early 1970s.