system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Where does that extra small storage in internal and external hard drives go?

1TB shows 940GB (my laptop)

128GB shows 100GB (my phone)

64GB shows 58/59GB (my USB Pen drive)

Where does that extra storage go? What takes that storage? Some hidden hidden files that are used to run that storage properly? If that's the case then why is there so much difference in that unaccessible storage from 5-50GB and more if you go beyond 1TB?
gpt
So, this is a bit of marketing mislabelling that technically is true but unintuitive.

There are two ways to measure storage. One is in powers of ten (like other SI units). A megabyte is 1000 kilobytes. A gigabyte is 1000 megabytes, and so on.

However there is a different storage base that is more sensible for computers: as powers of 2.

In this system a mebibyte is 1024 kebibytes. A gib is 1024 mib, and so on.


Marketing material uses the former is it appears larger. Windows uses the latter as it makes more sense. This makes it appear as the device is smaller than adverised. It isn't. Sure, some of it is index tables and reserved file system data, but a lot of it simply is that 1TB ~= 940gib or so.