ok, here we go, instant coffee was introduced into australia by the us army dudes before italian immigrants introduced espresso coffee. so the only coffee vocabulary people had was a flat white being: intant coffee - boiling water- dash of milk. so when coffee shops started popping up, the only coffee people knew was a flat white. of course the reply wouldbe "whatta the hell iz a flatta white?" to which replied: 'it's a white coffee' to which replied: "oh ok, no problem, cafe latte coming right up" from then on cafe lattes were served as flat whites and cafe latte were then put in various other vessels to differentiate the two. go to nz and most likely you'll get it in a bowl. where the glass came about, i'm still not sure of. in concern with those standards, 5mm = flat white, 10mm = latte....whatever. go to GJ's and ask for a flat white and you'll get just that. FLAT! when i was working at gj's u wouldn't stretch the milk at all, made a terrible noise, but the coffee was flat. if any customer whips out a tape measure and goes 'my latte has only 7mm of foam, it should be 10mm of foam' i'll just say " your 10mm of foam", and get on with making good coffee.