It's so simple. A fluid ounce is mainly used to measure the volume of fluids. The abbreviation that represents it is fl oz. There are many types of fluid ounces used, namely troy and avoirdupois. The mass of a fluid ounce of water is approximated as one avoirdupois ounce. This measures around 28.35 grams. Visit them on the
Askanydifference website and find out a lot of useful things for yourself. I've been reading articles there for half a year.
