Why Storage Devices Shows Less available Space Then The original Space?

In Most of the cases of storage devices We have seen that, The computer shows less space of the storage devices then the original space.
some times we think that it is the problem of our device or our computer or the device or the computer is infected by virus .
But do you think it is the main problem.
The answer is NO.

These are not the reason behind the problem.
And the matter of fact is this is not a big issue.
The companies that sold storage Devices consider the following.
1KB = 1000 Bytes
1MB = 1000 KB
1GB = 1000 MB
1TB = 1000 GB and more…
But the operating system or the computer consider the following.
1KB = 1024 Bytes
1MB = 1024 KB
1GB = 1024 MB
1TB = 1024 GB and more…
follow the example.
suppose you have bought a 16GB flash drive.
so according to the company it would be
16*1000=16000 MB and 16000*1000=16000000 KB and 16000000*1000=16000000000 BYET.
and when it will be divided by according to the computer system it should be 16000000000/1024=15625000 KB, =15258.7890625 MB, =14.90 GB.
so the actual available space for 16GB is 14.90GB.
and this is the reason why the Storage Devices Shows Less available Space Then The original Space.

THANKS.