Where did the dollar sign originate?

The dollar sign ($), commonly recognized as a symbol for various currencies around the world, most notably the United States dollar, has its origins in the Spanish-American peso. The sign descended from the Spanish coat of arms which depicted the Pillars of Hercules with a banner curling between them. The Pillars of Hercules were associated with the phrase "Plus Ultra," meaning "more beyond," which referred to Spain's exploration of the New World.

The most widely accepted theory is that the dollar sign is a result of evolution from the Spanish abbreviation "ps" for pesos, or "pesos de a ocho" (pieces of eight), which was a common currency in trade throughout the Americas and Asia. In handwritten documents of the time, the 'p' and the 's' were often written over each other to save space, which over time merged to become a symbol resembling an 'S' with one or two vertical strokes through it. This eventually led to the simplified design we are familiar with today.