Random Access Memory (RAM) is a type of memory inside the CPU where the data is temporarily stored. It is a volatile memory, which means that the data stored is not permanently saved will be erased when you shut down the CPU. However, the data stored here can be scanned quickly by the computer processor, thereby saving time.
Unlike the Serial Access Memory (SAM), where the data is accessed serially, in RAM, the data can be accessed randomly. This is the reason why more RAM leads to better performance.
How does the RAM work?
When you open a program on your computer or mobile, the program is loaded into the RAM from the hard drive. This makes it easier for the device to access the programs, and you do not feel the lag. Thus, it is also a sort of memory which collects the data that you need right at this very moment — be it the game that you are running or the video editing software that you are using.
RAM is made up of millions of transistors and capacitors, the latter stores the information in the form of 0s and 1s while the former acts as a control switch that helps in reading the data stored in the capacitors. In a Dynamic RAM, the information in the capacitors changes continuously leading to a slow reading process. Whereas in a Static RAM, the information is not refreshed continually, therefore it is fast and expensive when compared to Dynamic RAM.
So, in short, you can say that RAM is a storage device that stores only those programs that are currently running. Unlike the hard disks, RAMs have a speedier read/write time but are relatively costlier.
Types of RAM
There are several types of RAM, six of which are mentioned below.
- Static RAM (SRAM): This is primarily used in the cache as it is fast and therefore uses less read/write time along with consuming less power.
- Dynamic RAM (DRAM): In this RAM, each cell contains a transistor as well as a capacitor, and therefore, the information is refreshed continuously. These RAMs are slower and cost less. They are used in system and video memory.
- Synchronous Dynamic RAM (SDRAM): This RAM uses the burst mode and is synced at a speed of the CPU clock. Due to the syncing, it processes more information in less time.
- Double data rate synchronous dynamic RAM (DDR SDRAM): While the SDRAM performs one read, and one write instructions per second, the double data rate synchronous dynamic RAM performs two read and two write functions per second. Thus, making it twice as fast as its previous counterpart.
- CMOS RAM: This RAM stores CMOS information like the hardware settings of the computer or the date and time of the system, among others.
- Video RAM (VRAM): This RAM is used explicitly in the graphics card and provides details and depths to the videos.
Also read: What is ROM? Types of ROM and how it works