Reason behind why we get less capacity in storage devices :

Have you ever think that why we not got full capacity on any storage device like Pendrive,SD Card,Harddisk or any other storage device? for example if we buy a 2TB (2000GB) harddisk then we got only 1.81TB only. Some of us maybe thinks that this missing space is reserved by hardware or something else. but answer is really tricky. Actually here is fact behind this

because EVERY company counts:

1000 B for 1 KB
1000 KB for 1 MB
1000 MB for 1 GB and
1000 GB for 1 TB,

while its actually (1KB have 1024 B instead of 1000B) so this will be

1024 B for 1 KB
1024 KB for 1 MB
1024 MB for 1 GB and
1024 GB for 1 TB.

So lets do the company’s math: they think we need 21000100010001000 = 2.000.000.000.000 B to get 2TB. But thats wrong! If we reverse the math with the right numbers we get this: 2.000.000.000.000/1024/1024/10­24/1024 = 1,81TB

Thats why its only 1.81TB in 2TB harddisk. So whenever you buy new storage device you can estimate how much capacity you get in that.