Philip Stortz <madscientist.at.large@EARTHLINK.NET> wrote:
> can someone please define "big endian" and "little endian" for me, i
> understand that some machines have high byte first and small byte last,
> and some are the other way around, which of these are which when using
> the "endian" terminology?

"Big-endian" means the big end (MSB) of the number is at lower addresses,
while "little-endian" means the little end (LSB) appears first.

> fwiw, i have always preferred high to low value order of bytes, since
> that's the way we write ordinary human interpretable numbers, and it
> makes the most sense to me computationally.  obviously there must be some
> logical or implementation advantage to having them what i consider
> "backwards" that i don't understand or know, that information would be
> appreciated as well.

When adding or subtracting multiple-precision numbers, you need to start
processing at the little end of the number, so it makes a certain amount
of sense to store them little-endian so you get to that part first.

Also, if you number bits right-to-left within a word in the order of their
significance, it makes it more consistent to also number the byte/words in
order of their significance by storing them little-endian.

Intel, being first on the scene with single-chip microprocessors, chose
little-endian, for any or all of the above reasons. Motorola had to go
with big-endian in order to avoid patent problems.

-- Dave Tweed

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