the sign # is called NumberSign in UNICODE - which is, I believe, the standard attribution of numbers -from 0 to 255 or from1 to 256? to simbols to print
UNICODE is a rather than the standard, but it is a very important and widely used one. (The lovely thing about standards is that there are so many to choose from) It used to be a 16 bit standard allowing 65536 characters, but now has some extensions. It covers most current written languages and typographical symbols such as chess games, weather forcasts, etc., allowing most text to be unambiguously transmitted between systems.
From 0-127 UNICODE is identical to the ASCII designations. My Unicode manual (admitedly a little old now) gives 0023 (hexadecimal) as NUMBER SIGN and = pound sign as a subsidary usage. Note that this is a different character from the similar symbols of mathematical "Equal and Parallel to" at 22D5 and "Viewdata Square" at 2317. There is also a "Fullwidth" version of the Number sign at FF03 for use in Japan.
I'd completely forgotten I knew all this!
