Federal Reserve: The Federal Reserve, not the US Treasury, is responsible for issuing and regulating the nation's currency.
Presidential Portraits: The faces on US bills are exclusively those of former US presidents, except for Alexander Hamilton on the $10 bill.
Obsolete Denominations: In the past, the US has issued bills in denominations like $500, $1,000, $5,000, and $10,000, primarily for large transactions between banks.
Currency Redesign: The US periodically redesigns its currency to incorporate new security features and commemorate historical events.
Coins: US coins include pennies, nickels, dimes, quarters, and various commemorative coins, each with its unique design.
Digital Currency: In addition to physical currency, the US also embraces digital forms of payment, such as credit cards, mobile wallets, and cryptocurrencies.