uzziah0

E B,

I disagree with your explaination of things. I am not sure where your information comes from either.

I am an engineer, and have been in software engineering for over 10 years (my credentials).

I have never heard in engineering anyone say 1 KB is 1000! All engineers I have ever worked with say 1 KB is 1024.
It comes from base 2 numbering system, (binary, the 1s and 0s in the comuter world).

2 to the power of 10 = 1024 = 1 KB.

If you follow this you can probably jot out MB, GB and so on.

The reason you don't get the full advertised capacity of these devices is they have overhead to keep track of what is located where (just like hard drives).

The reason you lose more as your capacity increases (you loose more with 1 GB than 1 MB) is more complicated.
Memory used in this manner is divided into sectors. You can only create so many sectors (based on how the device is formatted - FAT16 or FAT32 - and the operating system).

If you are only allowed enough sectors so that on a 1 MB device you get 1 KB sized sectors (if you have 1 KB number of sectors; 1024 * 1024), you will have bigger sectors (because you get the same number) on a larger capacity device.
If you had a 10 MB device with the same number of sectors they would be tens times larger, 10 KB sized sectors.

If the device needed 1 KB for its overhead,
the 1 MB device allocates 1 sector, which is 1 KB;
but for the 10 MB device, it allocates 1 sector (it has to allocate the entire sector), which is 10 KB.