Need a quick and easy way to visually discover the difference between pounds and kilograms? Pounds to Kilograms Converter is the way to go! Simply watch conversions appear before your eyes as you slide up and down the measurement scale! Its that easy. You will soon discover general relations between pounds and kilograms visually. Pounds to Kilograms Converter is a great tool for both teacher and student alike! The standard kilogram is the mass which is equal to the International Prototype Kilogram. There are six copies of the standard kilogram which are stored at the International Bureau of Weights and Measures. There are different kinds of pounds (avoirdupois and troy or apothecary pounds). The word pound came from the Latin word pondus which means weight. lb comes from the Latin word libra which means scales.