[N.B.: Switch to a monopoint (fixed) font such as Courier, Courier New,
or Fixedsys when viewing this question.]

I'm all confused with file sizes! Someone please complete the following
table:

KILOBYTES (KB):     MEGABYTES (MB):      GIGABYTES (GB):     BYTES (B):
=======================================================================
1                   N/A                  N/A                      1,024
???                 1                    N/A                  1,048,576
???                 ???                  1                1,073,741,824
=======================================================================

Thanks!

Hello grandrascal-ga,

Thank-you for your question.

Conversion between different sizes in terms of computer storage is
confusing at times because unlike "real life" 1000 does not always
equal 1000 but is sometimes 1024!

The quickest way to complete this table is to use one of the excellent
online conversion calculators such as:
http://www.onlineconversion.com/computer_base2.htm
http://www.convert-me.com/en/convert/computer
http://matisse.net/bitcalc/

KILOBYTES (KB):     MEGABYTES (MB):      GIGABYTES (GB):     BYTES (B):
=======================================================================
1                   N/A                  N/A                      1,024
1,024               1                    N/A                  1,048,576
1,048,576           1,024                1                1,073,741,824
=======================================================================

I think most beginners agree this is a complicated and confusing way
of representing something that should be simple.

The confusion arises because computers work in binary.  Therefore the
nearest value to 1000 is 1024 or 2^10 (2^9 is 512, another "computer
number" that crops up a lot).  Similarly the nearest number to one
million is 1,048,576 (2^20).

For simplicity we remember that one MEGAsomething is one thousand
times larger than a KILOsomething, in computer storage one
MEGAsomething is actually 1024 times larger than a KILOsomething. 
Instead of using a new term we "steal" the terms KILO and MEGA and
apply this new definition of being 1024 times larger or smaller.

This means:
1 kilobyte is 1024 byte (not 1000 as you would mean in other areas of science)
1 megabyte is 1024 times (not 1000!) larger than a kilobyte, which
means it is 1024 kilobyte and 1024x1024 (1,048,576) byte.
1 gigabyte is 1024 times larger than a megabyte, which means it is
1024 megabytes, 1024x1024 (1,048,576) kilobytes and 1024x1024x1024
(1,073,741,824) byte.

Hopefully this is of some use to you, if you require any further
assistance please ask for clarification and I will try to explain a
little bit more.  The webpages in the "further information" section
below should also help you build up your background knowledge.

Further information:
http://en.wikipedia.org/wiki/Kilobyte
http://en.wikipedia.org/wiki/Megabyte
http://en.wikipedia.org/wiki/Gigabyte
http://en.wikipedia.org/wiki/Binary_prefix

Thanks very much! That helps to clarify things for me.   :)

Just to add to the confusion, there are several different definitions
for the big byte collections.
Under the SI classification, which is followed by the IEC, ISO and IEEE,
kilo, mega and giga are 10^3, 10^6 and 10^9. 2^10, 2^20 and 2^30 are
kibi, mebi and gibi.
Memory still tends to be quoted base 2 while hard disk space is most
commonly by base 10.
Apparently there is even a third megabyte of 1,024,000 bytes for the old 
(3 1/2 inch), "1.44 MB" floppy.
see the National Institute of Standards and Technology
http://physics.nist.gov/cuu/Units/binary.html

Thanks for the 5-star rating and tip!