A counterfeiter is someone who illegally makes fake copies of money, official documents, or valuable items, intending to pass them off as real.

Throughout history, counterfeiters have tried to trick people by creating phony bills and coins that look genuine. Modern governments fight counterfeiting by adding security features to currency: watermarks, special threads, color-shifting ink, and tiny details that are extremely hard to copy. If you look closely at a real U.S. $100 bill, you'll see Benjamin Franklin's portrait contains tiny writing that would be nearly impossible for a counterfeiter to reproduce perfectly.

Counterfeiting isn't limited to money. People also counterfeit designer clothing, sports memorabilia, artwork, and official documents like passports or tickets. A counterfeiter making fake concert tickets might sell them to unsuspecting fans who discover at the gate that their tickets are worthless.

Counterfeiting is a serious crime because it undermines trust in money and official systems. When counterfeit bills circulate, they can destabilize an economy and hurt innocent people who unknowingly accept fake money. In the United States, the Secret Service was originally created in 1865 specifically to combat counterfeiting, which had become a major problem after the Civil War.