One ounce weighs 28.35 grams. An ounce can also be measured as 1/16 of a pound. The term comes from the Latin word "uncia," meaning one-twelfth; in the old apothecaries' system of measurement, there were 12 ounces in 1 pound.
Comparing the weight of common objects helps to understand how much 1 ounce weighs. An ounce weighs about as much as a group of about 10 or 11 U.S. pennies put together, or just a little less than four 1-euro coins. The typical weight of a AA battery is about 1 ounce. A group of about 20 paperclips also weighs 1 ounce.