Or pronounciation.

Which reminds me of something a comedian with the last name of "Hughes" once said. While preparing for a trip to France, it dawned on her that in French, her entire name is silent.

Hmmm, I always thought it had something to do with the Old French usage of z in the plural of words ending with dentals, presumably representing [ts]... but I'm not sure I even know what I'm talking about here.

Speaking of ligative characters -- how about the German double-s character? This is a ligature of s and z, and my German teacher always called the character 'ess-zed' -- why is it thought of as a double s? And represented (by typists with no ess-zed key) as 'ss'?

It's thought of as a double s because it is a double s—at least it was in Fraktur type, where it originated. When most ligatures disappeared and people grew unused to graphic variants, it "read" visually as s+z. Fuller discussion here. (Compare the latter-day English misreading of the yogh as z, cf. here, and of the thorn as y, giving rise to such silliness as "Ye Olde Gift Shoppe.")

Thanks, and many thanks for that note about "Ye Olde..." I never had a clue as to the why of that, but it makes perfect sense now. (I always read that as "You Old Gift Shop" and never really grokked about that not being meaningful.)