> The bps vs. baud distinction is perhaps better illustrated by V.32 modems,
> which use QAM (quadrature amplitude modulation) to operate at 9600 bps using
> an 1800 Hz carrier.  Four bits are transmitted at a time (ingnoring the
> possible use of trellis coding), so there are sixteen symbols.  2400 of these
> symbols are transmitted per second, so the baud rate is 2400.  If the carrier
> frequency was considered significant in determining the baud rate, rather than
> only considering the symbol changes, the baud rate would have to be at least
> the LCM of 1800 and 2400, which is 7200.

The place I read was the earliest use of "baud" was for signalling flags on
ships.  If the person with the flags could give one signal per second, that
was one baud; the number of bits per second would depend upon the number of
different signals he could give, but the baud rate was the number of signals
per second.