How the US first installed an electronic fence along the southern border

US Customs and Border Protection traditionally operates at ports of entry and along US borders

CBP manages security at official border crossings and patrols areas between ports of entry to prevent unauthorized crossings. View details of the agency's mission, organizational structure, and approach to managing the United States' physical borders.

In June 2025, apprehensions of illegal border crossings at the US-Mexico border reached an all-time low

Total US-Mexico border encounters fell to just 25,228—the lowest monthly figure ever recorded by Customs and Border Patrol—with only 8,024 Border Patrol apprehensions and a single-day low of 136 detentions on June 28.

The history of ARPANET and how it helped the US military during the Cold War

President Dwight D. Eisenhower established the Advanced Research Projects Agency in 1958, which recruited scientists to design the first large-scale computer network to support the American military during the Cold War. Academics would use the network to communicate via email among several US research universities.

A history of the White House fence

Since it was occupied in 1800 by Thomas Jefferson, the White House has had a fence. From the original wooden post-and-rail fence to today's 13-foot high steel barrier, check out this brief timeline of the White House fence from the the building's...

The process of electronic funds transfer was approved in the US in 1978

An electronic funds transfer is the transfering of money from one bank account to another via computer-based systems. When it was first introduced, it was revolutionary. A video from 1980 aimed to explain the value of electronic funds transfer to consumers at the time.

How the US built the Interstate Highway system

As late as World War II, it took a well-prepared motorist roughly 10 days to cross America from coast to coast in a car. That all changed when the nation undertook its biggest public infrastructure project in 1956, the National Interstate and Defense Highways Act, initiating a 36-year, $114B mission to lay 41,000 miles of roads across America. Watch a smart overview here.

The first time the US federally barred immigration based on nationality

Watch this six-minute video to learn about the Chinese Exclusion Act of 1882, which was the first federal law to bar immigration explicitly because of nationality.

In 1974, Los Angeles’s Community Analysis Bureau built a smart city

Los Angeles utilized aerial imaging and cluster analysis to gather and interpret civic data, leveraging surveillance technologies developed by the Department of Defense during the height of the Cold War. Instead of being used for military purposes, data insights helped direct social services to high-poverty neighborhoods.

Nixon secretly recorded nearly 3,700 hours of conversations

The White House taping system was secretly installed on Feb. 16, 1971, beginning with the Oval Office and Cabinet Room, and later expanded to Nixon's offices, Camp David, and telephones.

The history and operation of SIGABA, the US counterpart of the Nazi Enigma machine

Developed by the US Army and US Navy, over 10,000 of these machines were deployed by the end of World War II to encrypt messages for the armed forces using three series of rotors. The device would continue to be used until the 1950s, while personal computers were shown to possess enough computing power to crack it by 2021.

Poems and stories inscribed on the walls of a US immigration island

What Ellis Island was to the East Coast, Angel Island was to the West. Just off the coast of San Francisco, this processing center became a detention center for those targeted by exclusionary immigration laws. Click here to read some of the stories left by the detained.

Watch how Sanger sequencing kickstarted the first generation of DNA sequencing

Sanger sequencing is a foundational DNA sequencing technology developed in 1977. The Nobel Prize-winning discovery uses fluorescent dyes at the end of DNA chains, which are sorted by length through electrophoresis, to determine the order of nucleotide bases.

US marshals were the first federal law enforcement officers

Established in 1789, US marshals carried out court orders, served subpoenas, made arrests, and collected fines—serving as the federal government's main law enforcement agency across the states for nearly a century before the creation of the DOJ.

Mail-in voting has been used in US elections since the Civil War

Americans have cast mail-in ballots for more than a century, but COVID-19 greatly expanded their use. Modern systems track ballots and often require signature verification, increasing access while maintaining election security.

Citizen scientist volunteers can help identify invasive species in wilderness areas

Launched in 2005 by the Center for Invasive Species and Ecosystem Health at the University of Georgia, EDDMapS allows users can document invasive species sightings in the US and Canada in a web-based mapping system. As of February 2026, EDDMapS has over 8.6 million records, all freely available for querying.

Some employers are using new technology to surveil remote workers

'Bossware' tools help employers make sure their remote workers aren't slacking off on the job, using surveillance technology to monitor employee computer activity and more.

Tiny solar-powered tags can now track monarch butterflies across North America

Monarch tracking began in 1935, utilizing low-tech methods to gain a better understanding of migration patterns as monarchs travel to central Mexico during the winter. Each tag weighs 60 milligrams and can be tracked via an app to provide insights into butterfly life cycles.

How scientists know invasive nutria were likely introduced to California by humans

Although native to South America, DNA testing of the semiaquatic rodents showed they are closely related to a population in Oregon, suggesting they were deliberately transported into the state. First identified in the San Joaquin Valley in 2017, the distance, terrain, and lack of nutria between the two regions has allowed researchers to rule out natural migration.

The canal became the first use of lock-and-lake system at a massive scale

The system centered around Gatun Lake, the largest human-made reservoir at the time, and two massive concrete locks that helped raise the ships 85 feet from sea level to the lake surface. The excavation was also the largest earth-moving project at the time, moving 240 million cubic yards of soil.

A secret airlift sent 14,000 Cuban children to the US

As part of the covert Operation Pedro Pan, roughly 14,000 Cuban children were quietly flown to the US in the early 1960s—often with no warning, no luggage, and no certainty they would ever see their parents again.

Radar saved the British Royal Air Force from Nazi air assaults

Radar technology—particularly the Chain Home early-warning system—enabled the RAF to detect incoming Luftwaffe raids up to 80 miles out, coordinate fighter deployments through the Dowding System, and achieve interception rates over 90%. This technological edge was pivotal in winning the Battle of Britain and halting Germany's air campaign.

A 1992 failed parachute test provided the hardware for the first mixed reality system

The Virtual Fixtures platform was developed to improve human dexterity by merging physical and virtual objects with haptic feedback from an upper-body exoskeleton. Tight budgeting and significant equipment needs nearly canceled the project, were it not for salvaging and repairing cameras and sensors from a smashed experimental parachute rig.

Long before Major League Baseball began allowing instant replay for balls and strikes, an umpire reluctantly used the technology to determine whether a hit was a home run, a move that inadvertently ushered in a new era for the sport.

A technological breakthrough altered how Billboard determined what was popular

Before 1991, retail stores manually reported sales to Billboard, which then used those figures as part of its calculations for its weekly charts. In 1991, the magazine began using Nielsen SoundScan, a technology that tracked every unit sold in participating stores, providing a more accurate picture of what consumers were actually buying.

Rachel Carson's 'Silent Spring' exposed the harmful effects of pesticides on food

The 1962 book warned against the use of DDT, a pesticide often sprayed over fields of crops, cautioning that it could be harmful if ingested in excessive amounts by humans. Some credit Carson’s book with inspiring the modern environmental movement and with encouraging the US to establish the Environmental Protection Agency in 1970 and ban the domestic sale of DDT in 1972. (Some readers may experience a paywall.)

The 2026 season will be the first to allow challenges on balls and strikes

The Automated Ball Strike (ABS) technology—first tested in the minor leagues and in MLB's 2025 spring training and All-Star Game—defines the strike zone rather than relying on individual umpires' interpretations of it. Rather than allowing ABS to determine every ball or strike, though, each team will now have a limited number of in-game challenges to umpires' calls, which will be settled by ABS.

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.

The US first hosted the World Cup in 1994, a tournament that lives in soccer infamy for its poor planning and the murder of Colombian player Andres Escobar, who'd accidentally scored on his own net.

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

Experimental hantavirus vaccines and therapies, still under development, have long been funded by the US military.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

A 2019 Facebook event called on attendees to "Storm Area 51, They Can't Stop All of Us," resulting in countless memes, the creation of a music festival, and eventually the arrests of those who did try to approach the area.

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

Discover the catastrophic consequences of a failure of the US electrical grid—something that is more likely than many Americans think.

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.

Hear about the 250-year history of the United States Postal Service, complete with some of its strangest deliveries, important innovations, and the figures that made it an American institution.

The United States has had a tumultuous relationship with Cuba since its 1959 revolution, highlighted by a nuclear crisis and a decades-long trade embargo.

The story of Dollree Mapp, whose legal challenge over her 1957 conviction for possessing "obscene material" led to a major strengthening of the Fourth Amendment

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

The first horror movie is believed to be George Méliès' 1986 short 'The Haunted Castle,' which pioneered the use of special effects

Abraham Lincoln was almost assassinated weeks before his inauguration as he traveled from Illinois to DC through Baltimore in 1861; it took two independent claims for Lincoln to be convinced the threat was real

In 1984, Operation Smash Hit intentionally crashed a 239-ton train into a nuclear waste canister at 100 miles per hour to prove the canister's safety, which remained completely intact and lost just 0.29 of its 100 pounds of pressure.

Fish populations in the Great Barrier Reef have increased after installing waterproof speakers on the ocean floor that played recordings of sounds from healthy coral reefs.

'Shogun,' a 1980s TV series, helped popularize sushi in the US by stimulating an American interest in Japanese culture.

'Grand Canyon of the Yellowstone,' a work by American painter Thomas Moran, inspired Congress to establish Yellowstone National Park.

Track the location of the Voyager probes, currently between 13 and 15 billion miles away from Earth.

Watch contemporary footage covering the US-backed Shah of Iran fleeing the country in the face of the 1979 Iranian Revolution

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

Before the current East Wing ballroom project, only two White House renovations in the past 100 years cost more than $10M.

The Beatles' US label rejected the band's first two singles, 'Please Please Me' and 'From Me to You,' with one executive calling the band 'dead in the water.'