Fake currency refers to counterfeit money that is produced to imitate real currency, such as U.S. dollars or euros. Counterfeiters use various methods to create fake bills, often employing advanced printing techniques to make them look authentic. The circulation of fake currency can harm economies and undermine trust in financial systems. Governments and law enforcement agencies work to combat counterfeit money through various measures, including the use of security features in real currency, such as watermarks and holograms. Individuals are also encouraged to be vigilant and check for these features to avoid accepting fake currency in transactions.