Why are there Latin words on US money?

Presumeably you are referring to the Latin phrases on the back of the one dollar bill. The pictures on the back of the one show the front and back faces of the great seal of the United States. The seal was designed shortly after the revolution. At that time Latin was the universal language of educated men. To know Latin was a sign of being genteel and sophisticated. Thus using Latin on the seal gace it an ense of seriousness and also permitted the ideas expressed to be read and understood by educated men from every country in Europe. The phrases are: "E Pluribus Unum" that means "Out of many, one" and is a reference to the several states joining together to form one nation; "Annuit Coeptis" which means "He favors our endeavors" which is a reference to the apparent favor that America has received from God since the founding; and "Novus Ordo Seclorum" which means "A new order for the ages," this is written immediately beneath the latin numerals for 1776 and symbolizes the historic nature of that date as the beginning of republican self rule in the world. Michael Montagne