For most people, an HDD or hard disk drive inside their computer is the flat broad box that stores their Operating System, files, documents, and other essentials. So far, not many users were aware of the inner workings of their HDD. Lately, with speeds of computers going up many folds, people have started looking at alternatives for the HDD – the SSD or the Solid State Drive.
Whatever else you change in your computer system, the general experience remains the same. For example, you may get a new display, add more RAM or install a new graphics card. Barring a few moments of exhilaration, you do not experience the constant euphoria that you get when you replace your regular HDD with an SSD.
An SSD suddenly transforms your computer into a high-speed demon. Additionally, you get this feeling every time you use the computer. Even if you do not realize this increase in speed with an SSD, you will appreciate it as soon as you have to revert to operating a computer with a regular HDD. It is truly amazing the way this new technology is helping to transform our computer experience.
To understand the functioning of SSDs, it is necessary to know the computer’s inner structure or architecture regarding its memory. A computer’s memory architecture is actually made up of three sections: the cache, the temporary memory and the actual memory storage itself.
The CPU or the Central Processing Unit of a computer is intimately connected to the cache memory and accesses it almost instantaneously. As the computer operates, the CPU uses the cache memory as a sort of scratch pad for all its interim calculations and procedures.
The temporary memory, also known as the RAM or Random Access Memory of a computer is the place where the CPU stores information related to all the active programs and running processes. Although the CPU can access the RAM at high speeds, the access is slower than that for cache memory.
For permanent storage, your computer uses the memory within the HDD or the SSD. These may be programs, documents, configuration files, movie files, songs, and many more. Unlike cache and RAM, an HDD or an SSD retains its contents even when the computer has been shut down.
When people replace their HDD with an SSD, their computer operates at a higher speed even when they have not updated their cache or RAM. This is fundamentally because of the difference in the way of working of an HDD and an SSD.
An HDD is essentially an electromagnetic device. Inside, there is a motor to spin the several magnetic platters stacked one on top of the other. Before the CPU can read data from the magnetic plates, they have to spin until the right sector comes under the reading heads, which then move in to read from the exact location. All this mechanical movement takes time.
On the other hand, the SSD, being an all-electronic device, involves no mechanical movements. It uses a grid of electrical cells to store and retrieve data. Moreover, these cells are further separated into sections called pages. Further, pages are clumped together to form blocks. All this contributes to the fantastic speed of an SSD.