The Grace Hopper subsea cable transmits internet traffic across the Atlantic

The 500 subsea cables that run the internet

Subsea cables carry the majority of data sent across the globe on the internet. An estimated 552 such cables—with more in development—lay on the ocean floor, their thickness similar to a garden hose, made up of optic fibers covered in copper.

Learn about the construction of the undersea fiber optic cables carrying internet data

Over 750,000 miles of fiber-optic cables run along the seafloor, serving as a freeway for the Internet's data. Despite subsea cable projects costing hundreds of millions of dollars, depending on the length of the cable, it remains the fastest and most cost-effective way to send information.

Explore a searchable map of underwater cables carrying internet traffic worldwide

The Submarine Cable Map provides users with data from TeleGeography's Transport Networks Research Service on individual submarine cables, including cable owners, suppliers, URLs, landing points, lengths, and notes of interest.

Around 380 underwater cables power the Internet across the world.

On July 29, 1858, two steam-powered battleships met in the middle of the Atlantic Ocean. There, they connected two ends of a 4,000 kilometer (2,500 mile) long, 1.5 centimeter (0.6 inch) wide cable, linking for the first time the European and North American continents by telegraph.

The transatlantic cable allowed for communications between North America and Europe

It had significant impacts on just about every industry, including finance. Specifically, the transatlantic cable made it so that real-time financial transactions could take place across the Atlantic, and allowed for much faster sharing of information that increased global market accuracy.

Watch Grace Hopper's appearance on the 'Late Show with David Letterman'

During this comedic interview, Hopper describes her 43.5 years in the Navy, an anecdote about when President Reagan promoted her, and provides a visual aid to explain the transmission of information at the nanosecond scale via electricity.

With a core consisting of a glass fiber roughly the width of human hair, fiber-optic cables transmit digital information via flashes of light that reflect within the glass.

The Grace Hopper Celebration honors women in computing every year

Since 1994, the world's largest gathering of women technologists has been produced by The Anita Borg Institute, a nonprofit driving intersectional equity in the global technical workforce. The event honors the legacy of Grace Hopper by highlighting the research and impact of women in technology.

Explore a collection of media depicting major milestones from the life of Grace Hopper

The gallery features Hopper's meeting with President Ronald Reagan, her attendance at the groundbreaking of the Grace Murray Hopper Service Center—a Naval data processing facility—and her Presidential Medal of Freedom ceremony.

For her contributions, Grace Hopper received more than 40 honorary degrees

Beyond the scholarships, professorships, and awards named in her honor, President George Bush awarded Hopper the National Medal of Technology in 1991 for her work in developing computer programming languages that enhanced accessibility. In 1996, Hopper became only the second woman to have a US Navy warship named after her.

NVIDIA named several computer chip architectures after Grace Hopper

Unveiled in 2023, the GH200 Grace Hopper Superchip, designed for generative AI applications in data center-scale systems, combines a Grace CPU with a Hopper GPU to create a coherent memory model. This allows the Hopper to access Grace data directly, reducing the need to repeatedly copy data back and forth and vastly improving performance.

SpaceX's Starlink is a satellite internet service that provides broadband internet by connecting users to satellites in low Earth orbit, which then communicate with ground stations connected to the internet.

The internet explained at five levels of difficulty, from protocols to internet flattening

Resembling a roadway with traffic laws that all cars must follow, the internet is the hardware that connects a source to a destination, and these connections must follow specific software rules. Although data had to travel through about 10 networks to reach a destination in the past, data centers increasingly consolidate traffic, just as a highway does for cars, to improve data speeds.

Grace Hopper described serving in the US Navy as the highest award she received

Despite retiring from the US Naval Reserve in 1966 at 60, as stipulated by Navy regulations, Hopper was repeatedly recalled for her pioneering expertise in computer science. By 1983, three years before her final retirement, she would give lectures about 200 days a year to computer scientists at military bases, college campuses, and businesses on behalf of the Navy.

Grace Hopper won the Data Processing Management Association's 'Man of the Year' award

The inaugural recipient of the award—symbolic of the male-dominated nature of computer science—was honored in 1969 for her contributions to the development of COBOL and the first compiler. Hopper would also become the first woman from any country and the first American to be recognized as a Distinguished Fellow of the British Computer Society.

President Barack Obama compared Grace Hopper to the Wright Brothers

When posthumously awarding Hopper with the Presidential Medal of Freedom—the nation's highest civilian honor—on Nov. 22, 2016, the former president remarked, "If Wright is flight, and Edison is light, then Hopper is code. [...] From cell phones to [US] Cyber Command, we can thank Grace Hopper for opening programming to millions more people."

The history of the National Science Foundation Network, a precursor of the internet

Although ARPANET connected various national laboratories and supercomputing facilities by the 1970s to facilitate scientific collaboration, the system was slow and required highly trained operators. The launch of NSFNET in 1986 provided a more flexible and powerful network that went on to connect over 170 academic and research communities and link to its European counterpart, EASInet.

In 2017, Yale renamed one of its colleges to honor Grace Hopper

Founded in 1933, the Calhoun College—one of Yale's 12 undergraduate residential colleges—was renamed to Grace Hopper College in honor of the woman who earned a master's degree and PhD in mathematics from the university in the 1930s. The change was also made to distance the school from white supremacist John C. Calhoun.

Grace Hopper warned against prioritizing hardware purchases in future computing

Foreseeing the rising volume of data and the increasing demand for its processing and access, she advocated that organizations first map the total flow of information they require and then choose infrastructure to support it, rather than wastefully spending on the fastest computing technology and forcing software to compensate for unnecessary hardware or incorrect data.

The Deep Space Network is an array of giant radio antennas at three locations on Earth to keep NASA in constant communication with spacecraft billions of miles away.

The wild, early history of the tunnel across the English Channel

Britain and France today are connected by the Chunnel—a tunnel bored roughly 120 feet under the seabed of the notoriously choppy English Channel, which opened in 1994. The dream of integrating Britain with the rest of the continent this way began much earlier, with daring, physically impossible plans proposed as early as the 19th century. Check out the earliest plans here.

When GPS and sonar are unavailable, submarine navigation relies on a fiber-optic gyroscope to determine the vessel's orientation and an accelerometer to calculate distance traveled.

The Worldwide LHC Computing Grid—a distributed system of 2 billion gigabytes of storage across over 40 countries—manages data produced by the Large Hadron Collider.

View a map of US data center infrastructure in 2025

Thousands of data centers across the country have already been built, with more under construction or planned. Facilities are connected via transmission and fiber optic lines, with the latter spanning an estimated length of 160 million miles.

View data center electrical demand and fiber optic cable connections across the US

Data center hub construction has prioritized locations with affordable electricity and fiber internet for data transmission, including Loudoun and Prince William Counties in Virginia and Maricopa County in Arizona. As of 2025, Northern Virginia's robust data center infrastructure is estimated to handle about 70% of global internet traffic.

The history of the commercialization of the internet, from ARPANET to NSFNET and beyond

NSFNET was launched in 1986 by the National Science Foundation as the first network available to all researchers, connecting them to a system of supercomputer facilities. Despite growing from 2,000 computers in 1985 to 2 million by 1993, the rapid expansion of commercial internet services led to NSFNET's decommissioning by 1995.

Grace Hopper was named the 1959 Time magazine 'Woman of the Year'

The honor was part of the 2019 series "100 Women of the Year," which spotlighted an influential woman for each of the years the publication had previously awarded a "Man of the Year." In its write-up, Hopper was described as having "paved the way for women everywhere to thrive in math, computer science, and service to their countries."

An explanation of TCP/IP, which helps transmit data across the internet like a club sandwich

The system consists of several layers—application, transport, internet, and network—each responsible for specific tasks. These include interacting with a web browser, checking for errors, sending packets of data across various networks to avoid congestion on their way to a destination address, and managing the transmission of information across hardware, such as an Ethernet cable.

Testing the internet speed of the US's wireless providers

The US ranked 26th in the world for mobile speeds and eigth for fixed broadband speeds during April 2022. See this ranking of mobile and fixed broadband speeds from around the world on a monthly basis.

Explore coral reefs in Google's "street view"

Expanding its mission to map the world, Google Maps partnered with The Catlin Seaview Survey to introduce the first-ever underwater panoramas, making oceanic marvels like the Great Barrier Reef accessible to everyone. With Google Maps, the public...

Learn about the protocols that make navigating the internet possible

While TCP/IP sends data in packets to the correct destination and checks for errors, UDP omits such safety features to speed up data transfer for real-time communication and streaming. Software rules such as HTTP and HTTPS enable the transfer of content on the World Wide Web, while SMTP handles email messages between servers.

The world's maritime traffic in real-time

More than 50,000 ships are sailing the high seas on any given day, representing the highest volume pathway for international trade. This real-time traffic provides a visual impression of the scale of ocean-bound commerce.

What we learned about Google

Google processes over 8.5 billion searches every day—more than the number of people on Earth. This short breakdown covers how the company evolved from a Stanford research project into a global tech leader, with products like YouTube, Gmail, and Android reaching billions worldwide.

A US Department of Defense research lab developed the technology for the dark web

Although encryption existed to mask the content of communications across the internet before the 1990s, those managing overseas network infrastructure could determine a spy's affiliation based on where they saw data sent to and received from. To keep this information secret, the US Naval Research Laboratory developed onion routing, which enabled anonymized web browsing. The release of the technology to the public obscured sensitive communications further by growing the volume of anonymous data.

Which countries have the fastest internet speeds?

Ever wonder about how fast internet speeds are around the world? Take a look at this graphic which lists out the countries with the highest mobile internet speeds in 2023. Countries in the Middle East and East Asia dominate the list while America lags behind in eighteenth place. Learn more about why a high-income country like the US fall behind in speed, and why other countries are internet powerhouses.

Google only sorts and searches a fraction of the overall internet

The "surface web," consisting of billions of public webpages, excludes nonindexed digital content, such as corporate intranets and email inboxes. A deeper layer, called the dark web, is also hidden and requires special software to access.