United States dollar
The dollar was first based on the value and look of the Spanish dollar, used widely in Spanish America from the 16th to the 19th centuries. The first dollar coins issued by the United States Mint (founded 1792) were similar in size and composition to the Spanish dollar, minted in Mexico and Peru. The Spanish, U.S. silver dollars, and later, Mexican silver pesos circulated side by side in the United States, and the Spanish dollar and Mexican peso remained legal tender until the Coinage Act of 1857. The coinage of various English colonies also circulated. The lion dollar was popular in the Dutch New Netherland Colony (New York), but the lion dollar also circulated throughout the English colonies during the 17th century and early 18th century. Examples circulating in the colonies were usually worn so that the design was not fully distinguishable, thus they were sometimes referred to as "dog dollars".

Q: What was the look of the dollar based on?
Spanish dollar