Why actual capacity is lower than printed capacity in Storage devices?

This is my first article of this blog. Sometimes you may have face to this problem when using storage devices like Hard Disk, Pen Drive. Standard units of measuring capacity are as follow.

•        8 bit     = 1 byte
• 1024 bytes = 1 KB (1024 Bytes)
• 1024 KB     = 1 MB (1024 x 1024 Bytes)
• 1024 MB    = 1 GB (1024 x 1024 x 1024 Bytes)
• 1024 GB     = 1 TB (1024 x 1024 x 1024 x 1024 Bytes)

These are in the form of 1024 to the power of 2.

But when producing these memory devices in factories, those units are changed as follow to calculate easily.

• 1000 bytes = 1 KB (1000 Bytes)
• 1000 KB     = 1 MB (1000 x 1000 Bytes)
• 1000 MB    = 1 GB (1000 x 1000 x 1000 Bytes)
• 1000 GB     = 1 TB (1000 x 1000 x 1000 x 1000 Bytes)

Namely they are in the form of 1000 to the power of 2.

As an example ; 5 GB = 5000 MB = 5000000000 Bytes(5 x 1000 x 1000 x 1000).
But after plug(attach) the device into USB port of a computer, computer translate those Bytes into Gigabytes by dividing it by 1024 to the power 3(1073741824 Bytes). Then computer display that final answer(5 GB = 4.65 GB).
So we can see that there is a difference between printed capacity and actual capacity and actual capacity is lower than printed capacity.
Until come from another important article, So much... Good Luck...!!

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