In 1990, the $100 bill became the first U.S. banknote to receive two modern anti-counterfeiting upgrades: an embedded security thread and microscopic printing.

The features were introduced to combat increasingly advanced copiers and printers. By Series 1993, they had been added to every U.S. denomination except the $1 and $2 bills.

Sometimes the smallest details provide the strongest proof—explore authentic currency at ThePatriotVault.com.