Warp wrote:
>   Btw, I have never understood why "kilobit" is so popular of a term.

It's a PSTN term. I.e., it's used in communication mediums like the public 
switched telephone network where data isn't always byte-aligned. For 
example, an American T1 circuit delivers 193 bits per frame.

Nowadays, it's more common to pad things out to the byte, since line speeds 
are much higher. Nobody really tries to speed things up by using 5-bit 
characters any more, so the need for kilobits is lessened.

Of course, audio is still in kilobytes per second, where a kilobyte is 1000 
bytes and not 1024.

> in order to comprehend the meaning. (Of course an easy approximation would be
> to divide by 10... assuming the 25% error isn't significant in the context.
> In many contexts that's a huge error.)

The 25% is probably insignificant if the kilobits is communication speed, 
because you have TCP overhead, framing overhead, etc.

>   The only rational reason for using kilobits rather than kilobytes would
> be if you need to express sizes which are not multiples of 8 bits. However,
> in practice that's *never* the case.

Not any more.
http://en.wikipedia.org/wiki/Baudot_code

Of course, on serial lines, you have start bits and stop bits, so you're 
really sending anywhere between 9 and 12 bits per character, sometimes 
including even half-bits.

> All practical sizes in computing are
> multiples of 8 bits. There's absolutely no reason to use kilobits. There's
> unnecessary accuracy in the unit.

Again, yes, that's true now. Once people started mass-producing machines, 
and the software got to where it was reasonable to run software from one 
machine on another machine, 8-bit seemed to become most popular.

The intel 4004 was four bits, the PDP-8 was 12 bits, etc.  Nowadays, 
machines are powerful enough that you have protected memory mapped virtual 
memory capable machines sitting in boxes with no user interfaces on them.

-- 
   Darren New, San Diego CA, USA (PST)
   Insanity is a small city on the western
   border of the State of Mind.

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