Steven wrote:
>
> I have seen it everywhere (pull all unused output lines to 5 volts). OK what
> if you dont do this? I have one curcuit that seemed to work fine and I did
> not pull the outputs up.
>

Whatever else you do, don't ever pull OUTPUT lines to 5v (or 0v),
unless you do it through a resistor. Input lines can be tied
directly, but this can still fry you if you accidentally configure
the pins as outputs later.