The conversion factor from pounds to ounces is 16 (for troy weight, it is 12). Pound is a unit of mass in U.S customary, imperial and other different measurement systems including the historical ones (Romans called it "libra" and that's why it's abbreviated as "lb" and "lbs" today). After the metric system is accepted in many countries, it's replaced with "kilogram" but it's still one of the most common weight units in US, UK, Canada and a few other countries.

Ounce is used as a unit of mass in imperial and U.S. customary measurement systems. It is also used as a volume unit but in this case, fluid ounce is referred. The abbreviation is "oz".