Every printed bill has its own unique serial number

Each design detail on the US $1 bill has significance

The eye in the triangle floating above the pyramid, for instance, is “the Eye of Providence watching over and ensuring the endurance of the structure of the American government.” This article details every design choice’s significance on the dollar—and a few conspiracies around these choices as well.

The Australian $5 bill has an image of a bird that glows when exposed to UV light

That’s just one of the many anti-counterfeiting security measures that the Australian government implements on its currency. Popular banknotes from around the world all include their own unique security features—this infographic outlines a few unique ones.

The $1 bill hasn’t been redesigned in over 60 years

From a counterfeiting and forgery perspective, this makes the $1 bill one of the least secure American banknotes. In this video, the Wall Street Journal sits down with a leading currency expert to explore the techniques used to keep cash safe and figure out what's going on with the $1 bill.

During the Civil War, the US government printed paper money for the first time

Those original paper bills were called “greenbacks” or “demand notes.” Since then, paper money has evolved with different designs, names, and values. Today, it is solely issued by the Bureau of Engraving & Printing.

The United States had a washing machine that cleaned dirty dollar bills

In the early 1900s, the US Treasury Department had a machine that washed and ironed old, soiled paper bills. The machine helped the Treasury save money by decreasing printing costs for new dollar bills, but had nothing to do with the modern understanding of money laundering.

How US currency is issued

Cash in the US is the result of a collaborative process between the Federal Reserve, the Treasury Department, regional banks, and a little-known agency called the Bureau of Engraving and Printing. From design to issuance, learn the steps in currency production in the US with this smart, aesthetic interactive.

The US Currency Education Program created a guide to authenticating currency

This video was created to teach everyday people a few easy ways to spot some counterfeit banknotes. Specifically, it outlines the main security features to check for that are common across many US banknotes, such as the color-shifting ink visible when tiling US banknotes $10 or higher.

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'

The US once had a $100K bill

There are currently seven denominations of paper money, with the highest value reaching $100. But there used to be more that have since been discontinued, including bills that sported the faces of President William McKinley and President James Madison.

Some coin denominations have ridges on their sides in part to prevent counterfeiting

You may have noticed that dimes and quarters feature small ridges on their sides that other coins, like pennies and nickels, don't have. This video can help you learn more about why the practice, called "reeding," was first started—and why it's still used today.

The 'Where's George?' project tracked a trail of $1 bills across the US

Over a decade ago, a group dedicated its time to tracking $1 bills in the US. They would stamp single bills with the phrases “currency tracking project” and “Track me at WheresGeorge.com” in a practice they dubbed “Georging.”

Today, in the US, people can face years in prison for counterfeiting money

There are both federal and state laws that punish people who use or create counterfeit money. The crime can not only trigger hefty fines, but could also lead to decades behind bars.

The Secret Service was originally formed to combat counterfeiting

By the 1860s, an estimated one-third of US currency in circulation was counterfeit. In 1865, the Secret Service was created specifically to combat the country's serious counterfeiting problem, which had led to widespread financial instability. This was partly due to the lack of federal currency standardization in the country at the time.

Microchips in payment cards improve security by generating unique transaction codes

Magnetic strips store unchanging data that is easily cloned, but microchips act as miniature computers that encrypt sensitive data. They also resist fraud by creating data unique to each transaction, preventing duplication.

Contrary to popular belief, the $2 bill is still in circulation today

However, it is far less common than other bills. Usage of the $2 bill has been in decline for decades, but the US Treasury hasn’t retired the bill yet. A podcast episode from the Fed’s educational program explains why the Treasury doesn’t print new $2 bills every year, and why they're still considered legal tender.

The Federal Reserve follows the health of the US economy by tracking the money supply

That includes all of the physical and electronic money in circulation. It tracks not only US coins and bills, but also the money that moves through bank deposits. The Fed uses metrics called trackers to follow different types of transactions through the money supply.

Treasury bonds, notes, and bills are critical vehicles for the federal government to raise money for public expenses and manage the national debt

For investors, they're all usually considered low-risk options since they’re backed by the federal government.

Watch 'I'm Just a Bill' explain how a law gets made

First aired in 1976, "I'm Just a Bill" became a defining civics lesson for generations, using animation and humor to trace the legislative process and cement itself as a lasting piece of US political culture.

10 of the original 14 copies of the Bill of Rights still exist

Clerks produced 13 copies for the states, plus one federal copy. Today, eight states still hold theirs. Georgia's and New York's were likely burned, Pennsylvania's was stolen, and Maryland's whereabouts remain unknown.

The House of Representatives controls the $7T federal budget

The House holds the exclusive "power of the purse" to initiate revenue bills, a provision in the US Constitution designed to divide power with the Senate and give states with larger populations greater influence over federal budgeting.

NFTs create a unique digital signature to prove ownership

NFTs create digital certificates for unique online collectibles, mainly on the Ethereum blockchain. Artists can leverage NFTs to verify their online works.

See how the concept of verification and addition to the blockchain works in real time.

Every transaction made via bitcoin is recorded on its blockchain—the decentralized, distributed ledger that provides a permanent and transparent record of the currency's entire history. While that may sound abstract, the technology allows anyone to monitor and confirm each of the transactions.

Calculate the value of a paper savings bond

An IRS tax refund is the only way to buy a paper savings bond, but if you have an old paper savings bond you can determine its current value with this calculator. The calculator only works for paper savings bonds of Series EE, Series I, Series E, and savings notes.

Making sense of the parts of a check

Though individuals use checks sparingly if at all, half of businesses rely heavily on check-writing to pay suppliers and contractors. Get to know the parts of a check with this visual guide.

The Depression-era Social Security program assigned every US citizen an account number

Many of the Social Security functions we know today are the result of multiple amendments to the Social Security Act that have been passed in the years since the act’s initial creation in 1935. As Social Security as we know it today was being conceptualized, Democrats opted to make it an insurance program rather than a welfare one to assuage Republicans.

The US dollar is the most widely circulated currency in the world, and is involved in nearly 90% of global transactions

The original copy of the Declaration of Independence is not a pristine document, and even features a smudged anonymous handprint in the bottom left corner.

In addition to collecting taxes, issuing tax refunds, and performing audits, the IRS is tasked with enforcing the laws listed in the Internal Revenue Code

The Internal Revenue Code is also known as Title 26 of the US Code. It was enacted in 1925 and outlines income, estate, sales, payroll, and excise tax laws.

Explore fun facts from the USPS, including unique post office buildings, a stamp that traveled past Pluto, and more.

US consumers collectively owe more than $1T to credit card companies—almost as much as they owe in auto loans.

The idea for the Federal Reserve was conceived in secret in 1910—with bankers donning duck hunt gear for disguise while traveling to a remote country club on Georgia's Jekyll Island

A century of Billboard issues documenting the evolution of popular music.

Calculate how much of your tax dollars go to each federal program based on your income, filing status, and number of children

The US Constitution is widely regarded as the longest-standing written national constitution still in force—see how it has influenced rights worldwide.

Art theft is the third-largest source of criminal revenues worldwide, thanks in part to the subjective nature of valuing a work of art.

Learn how to read a prospectus, the juicy document that any company must file with the SEC before going public.

Tattoos remain visible on your skin thanks to immune cells called macrophages

According to the physics of black holes, our 4D reality may be a hologram—a projection of information coded on a 2D surface on the edge of the universe.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

Planarian flatworms are small, aquatic worms with exceptional regenerative capabilities. When cut, the worms can regenerate multiple bodies in a matter of weeks.

Ebola species have historically been named after where they were discovered, stigmatizing residents who live there, including Bundibugyo, in Uganda.

Massive 3D printers have been used to build homes by stacking layers of 'concrete toothpaste,' a fire-resistant material that effectively insulates against outside noise.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

The animatronic shark from Steven Spielberg's 'Jaws,' the first modern blockbuster, was a complex underwater apparatus called 'Bruce.'

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

When you complete a CAPTCHA on a website to prove you are human, you may be unknowingly training algorithms for self-driving cars, whose systems require training data to help identify crosswalks, bicycles, and other outdoor objects.

Lesser-known phobias include turophobia, or the fear of cheese, and nomophobia, the fear of being without your cell phone.