When it comes to computer storage, there is often confusion and discrepancy between the advertised capacity and the actual usable space displayed on the operating system. This is due to the way storage is calculated and the difference in measurement units used by manufacturers and operating systems.
Firstly, let’s clarify the units of measurement commonly used in storage. In the context of computer storage, the base unit is the byte, which represents a single unit of digital information. From there, we have kilobytes (KB), megabytes (MB), gigabytes (GB), terabytes (TB), and so on.
In the decimal system, which is used by storage manufacturers, each unit is based on powers of 10. For example, 1 KB is equal to 1000 bytes, 1 MB is equal to 1000 KB, and so on. Therefore, a 512GB hard disk drive manufactured and marketed by a storage company will be calculated as 512,000,000,000 bytes.
On the other hand, when it comes to operating systems like Windows 10, the binary system is used for storage calculations. In this system, each unit is based on powers of 2. So, 1 KB is equal to 1024 bytes, 1 MB is equal to 1024 KB, and 1 GB is equal to 1024 MB. Therefore, 512GB on the operating system will be calculated as 512,000,000,000 bytes / (1024 bytes/KB * 1024 KB/MB * 1024 MB/GB) = 476,837,158.2 GB.
The difference between the advertised capacity and the displayed capacity on Windows 10 can be attributed to this discrepancy in measurement units. The storage manufacturer advertises the capacity using the decimal system, while the operating system calculates and displays the capacity using the binary system.
Additionally, the displayed capacity on Windows 10 is further reduced due to formatting and system files. When a hard disk drive is formatted, a small portion of the total capacity is reserved for file system structures and metadata. This is necessary for the operating system to organize and manage the files on the disk. The amount of space reserved for formatting can vary depending on the file system used (such as NTFS or FAT32), but it typically ranges from a few gigabytes to several gigabytes.
Moreover, the operating system and various software installations also consume some space on the hard disk drive. This includes the Windows installation files, system updates, drivers, applications, and temporary files. These files can take up a significant portion of the disk space, further reducing the displayed capacity.
To summarize, the difference between the advertised capacity and the displayed capacity on Windows 10 is primarily due to the difference in measurement units used by storage manufacturers and operating systems. The binary system used by the operating system leads to a lower displayed capacity compared to the decimal system used by manufacturers. Additionally, formatting and system files also contribute to the reduction in usable space.