The tutor attempts to explain a possible misunderstanding.

A few days ago I posted about buying my kids each a 16GB flash drive by PNY. Today I showed my younger kid how to access it on Windows (he’s used to Mac from school).

“Why does it say 14.8GB, when it’s 16GB?” he asked.

Of course, it’s an obvious question. I’d say there are two reasons for the apparent discrepancy. The lion’s share of the difference can be accounted for by the fact that, in computer science, 1kilobyte, or 1kB, is not actually 1000 bytes; rather, it’s 2^10=1024 bytes. In that same context, 1GB=(1kB)^3=(1024)(1024)(1024)=1 073 741 824 bytes. It’s about 7 percent more than the flat 1 000 000 000 bytes that the prefix “giga” would normally suggest. (Comp-sci people have their own definitons for the prefixes such as kilo and giga.)

Therefore, from a comp-sci point of view, 14.8GB=14.8(10737741824)=15 891 378 995 bytes. That’s 15.89GB, from the standard definition of “giga”. So, 14.8GB (comp sci) = 15.89GB (normal “giga”).

The other “missing” 0.11GB, I suspect, is used in formatting. When storage space is prepared to receive data, it’s organized internally. That organization – called formatting – takes up some memory.

So, if the 16.0GB statement on the box means 16 000 000 000 bytes, the claim seems correct. It’s just that, in comp sci, “gigabyte” means 1 0737 741 824 rather than 1 000 000 000 bytes. That’s how, internally, 14.8GB resolves to the 16.0GB printed on the box.

HTH:)

Jack of Oracle Tutoring by Jack and Diane, Campbell River, BC.