Name: The Battle Between Captcha and AI Is Heating Up | WSJ Tech Behind
Uploaded: 2024-11-12T05:01:00Z
Duration: 7 min 25 s
Description: What began as a simple text to prove you aren’t a robot has rapidly evolved into a battle between humans and AI. WSJ explores the latest Captcha technology, and why AI algorithms may always get the upper hand.

https://www.barrons.com/client

Topics

Memberships

Tools

Customer Service

Network

Newsstand

For Business

For Education

For Advertisers

Account

About Barron's

bolded

unBolded

"We're trying to build an infrastructure at a pace the world has never seen before," Said Mike Intrator, CEO of CoreWeave. This interview was recorded on Jan. 21, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260130/9fefeb96-21f1-4462-b112-3aaca3722949/1/hls/manifest-hd-wifi.m3u8

CoreWeave CEO on Whether the AI Boom Is a Circular Economy

"The promise of AI is starting to get traction," said Mike Intrator, CEO of CoreWeave. This interview was recorded on Jan. 21, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260130/d1a78d1d-5153-453e-b4f6-6071639a1866/1/hls/manifest-hd-wifi.m3u8

CoreWeave CEO on the Future of the 'AI Economy'

"Nvidia has been an absolutely incredible partner for CoreWeave," said Mike Intrator, CEO of CoreWeave. This interview was recorded on Jan. 21, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260130/d8bc483e-3a75-466a-8e14-6c1712b12f14/1/hls/manifest-hd-wifi.m3u8

CoreWeave CEO on the Company's Relationship With Nvidia

Mike Intrator, CEO of CoreWeave, discussed the company's investments in self-built data centers, as well as third-party infrastructure. This interview was recorded on Jan. 21, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260130/3116ef6f-8fc2-43d8-a8e5-1c7b2aa839a4/1/hls/manifest-hd-wifi.m3u8

CoreWeave CEO on the Company's Data Centers

Mike Intrator, CEO of CoreWeave, explained why the company's relationship with Nvidia is "symbiotic but not equal," the future of the AI economy, and more as part of a conversation with Barron's editor at large Andy Serwer. This interview was recorded on Jan. 21, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260129/92afbff0-1175-4030-a383-f6a94b7dd910/2/hls/manifest-hd-wifi.m3u8

CoreWeave CEO on Nvidia, AI, and Building the Cloud

Joseph Dominguez, President and CEO of Constellation, discussed global aspects of the energy business. This interview was recorded on Jan. 20, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260122/dbf8069d-2eb7-4993-95e2-df86725f078f/1/hls/manifest-hd-wifi.m3u8

Constellation CEO on Transmitting Energy Globally

Joseph Dominguez, President and CEO of Constellation, discussed the future of the electric vehicle industry. This interview was recorded on Jan. 20, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260122/669e068f-d199-4ee5-9376-7eb2e8a83461/1/hls/manifest-hd-wifi.m3u8

Constellation CEO Sees Steady Growth for EV Demand

Joseph Dominguez, President and CEO of Constellation, discussed President Donald Trump's call for an emergency power auction. This interview was recorded on Jan. 20, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260122/52e7ac58-b132-4bcb-b752-a15c6e189bb5/1/hls/manifest-hd-wifi.m3u8

Constellation CEO on Trump's Plan to Cut Mid-Atlantic Electrical Bills

This level of energy demand has not been seen "in a long period of time," said Joseph Dominguez, President and CEO of Constellation. This interview was recorded on Jan. 20, 2026, at the World Economic Forum meeting in Davos, Switzerland.

https://m.wsj.net/video/20260122/082972b7-68f3-4df5-978c-7da79ff3fd50/1/hls/manifest-hd-wifi.m3u8

Constellation CEO on What Hyperscalers Mean For the Energy System

At Barron's

"Your 9-5...is just not going to do it," Nick Magguilli, personal finance expert, said on Barron's Streetwise podcast.

https://m.wsj.net/video/20251216/e6897805-d131-4cc4-9c59-ca03b0c0b958/1/hls/manifest-hd-wifi.m3u8

How to Scale Your Net Worth

TJ Thornton, Head of Global Research Product Marketing at BofA Securities, talks to Jack Hough about his favorite stocks outside of AI.

https://m.wsj.net/video/20251210/f9c1a95c-5a0e-4349-9fe4-73b3ac53bfb8/1/hls/manifest-hd-wifi.m3u8

BofA’s Favorite Non-AI Stocks

Jack Hough talks to TJ Thornton, Head of Global Research Product Marketing at BofA Securities about diversifying stocks to hedge AI risks.

https://m.wsj.net/video/20251210/8e164ff7-1500-4c2f-8713-e891c640a0f4/1/hls/manifest-hd-wifi.m3u8

Evaluating Investing Opportunities Beyond AI

Steve Quirk, chief brokerage officer at Robinhood, breaks down the value of tokenizing stocks in different markets.

https://m.wsj.net/video/20251126/f86d65ea-bd8b-4777-b6b0-80f7bb12027e/1/hls/manifest-hd-wifi.m3u8

Unpacking Tokenization for Everyday Investors

Jack Hough talks to Steve Quirk, chief brokerage officer at Robinhood, about trends in retail investing.

https://m.wsj.net/video/20251126/a9cbdcc6-f060-4fc9-a15e-396924e25946/1/hls/manifest-hd-wifi.m3u8

How Robinhood Reshaped the Trading Landscape for an Entire Generation

Streetwise host Jack Hough sat down with strategist Scott Wren to discuss how the AI-fueled market run stacks up against the dot-com boom.

https://m.wsj.net/video/20251111/bd2e1a5b-1a6e-4543-8133-dcc63f69b5dc/1/hls/manifest-hd-wifi.m3u8

AI vs. The Dot Com Bubble

Bank of America’s Haim Israel shares what’s next for Nuclear Energy development.

https://m.wsj.net/video/20250930/ab4fc336-af44-4af2-8e40-9ae6f04a445e/1/hls/manifest-hd-wifi.m3u8

The Outlook For Nuclear

Jack talks to Lyft CEO David Risher about growth potential in the company.

https://m.wsj.net/video/20250929/ae62b70e-912b-4ce7-ae63-1b2652628bae/1/hls/manifest-hd-wifi.m3u8

Lyft's Ride to Profit

The stock market is expensive. What does that mean for your portfolio? Jack sits down with Franklin Templeton’s Matt Quinlan to talk dividend investing, and whether it’s a good move in a pricey market.

https://m.wsj.net/video/20250911/9c85e132-d710-4458-9467-aa69d4f25ae0/1/hls/manifest-hd-wifi.m3u8

Dividends and Capital Appreciation

Barron's Streetwise

Anthea Tjuanakis Cox, Morgan Stanley’s head of financial planning, discusses key trends that advisors should consider when offering clients financial advice.

https://m.wsj.net/video/20260127/2debf803-64bf-4584-81dc-c92da72b7ed3/1/hls/manifest-hd-wifi.m3u8

Five Trends ‘Coalescing’ in Wealth Management

Interviews with top wealth management professionals about topics including compensation, hiring, marketing, next-gen, and more.

Advisors who can successfully serve a family with starkly different priorities represents the "alpha" that deepens the value of financial advice, says Anthea Tjuanakis Cox, Morgan Stanley’s head of financial planning.

https://m.wsj.net/video/20260127/2fd71263-ad5a-47f3-b7b8-9f784fd5f557/3/hls/manifest-hd-wifi.m3u8

Reconciling Divergent Values in Multigenerational Planning

For younger clients, advisors should discuss immediate life goals, not just distant  milestones, says Anthea Tjuanakis Cox, Morgan Stanley’s head of financial planning. “‘Make sure that you bring in the things that are actually relevant now.”

https://m.wsj.net/video/20260127/a12a45bb-eb55-40ec-bdaa-03cf9e74c32c/1/hls/manifest-hd-wifi.m3u8

Generational Differences and Advising Digitally Native Clients

Anthea Tjuanakis Cox, Morgan Stanley’s head of financial planning, says that when providing financial planning, advisors should offer multiple scenarios to reduce client anxiety and ensure that all parties involved feel seen.

https://m.wsj.net/video/20260127/ffcd128f-79e9-4cdc-b902-43c7667db536/1/hls/manifest-hd-wifi.m3u8

Advisors Should Share ‘Multiple Versions of Reality’ With Clients

“When you are with a prospect, a client, or a center of influence—anyone who has the ability to connect you—use the word introduction or connection,” says Bill Cates, founder of Referral Coach International.

https://m.wsj.net/video/20260113/61e36ad7-2500-42fb-abff-a52ca20310e8/1/hls/manifest-hd-wifi.m3u8

Why Advisors Should Embrace the Word ‘Introduction’

Bill Cates, founder of Referral Coach International, explains how advisors can learn more about their clients and build trust in the process.

https://m.wsj.net/video/20260113/ce45e37f-bb13-4b0c-896f-c7068a9e3fa0/1/hls/manifest-hd-wifi.m3u8

‘Three Magic Words’ That Advisors Should Say to Clients

“True relevance is all about empathy and really knowing your market and really knowing the people you are trying to reach,” says Bill Cates, founder of Referral Coach International. “That builds trust.”

https://m.wsj.net/video/20260113/85e0ebeb-a785-4705-b6af-5525daba48fd/1/hls/manifest-hd-wifi.m3u8

Relevance, Empathy, and Trust

Bill Cates, founder of Referral Coach International, describes how financial advisors can distinguish themselves from competitors.

https://m.wsj.net/video/20260113/bcc0f384-0f4a-4f62-bce9-6526a43e8948/1/hls/manifest-hd-wifi.m3u8

What’s Your Differentiator?

Although the northeast is still a “very strong market,” advisors and wealthy clients have been moving to the Southeast since Covid, says Jeff Gonyo, head of Wealth Management at Steward Partners.

https://m.wsj.net/video/20251229/3365335d-5a6e-435b-8ac2-df76d0ebcb93/1/hls/manifest-hd-wifi.m3u8

Advisors and Wealth Are Shifting to the Southeast

Barron's Advisor The Way Forward

Emily Green, head of wealth management at Ellevest, discusses the company’s intensive approach to training advisors on alternative investments.

https://m.wsj.net/video/20260122/3a98e5d9-ae20-4526-ae91-8a3df74c93a0/1/hls/manifest-hd-wifi.m3u8

How Ellevest Works With Advisors and Alternative Investments

Clients are concerned with the timing of distributions and the after-tax return of a fund and focus more on the value they receive than a fund’s fees, says Emily Green, head of wealth management at Ellevest.

https://m.wsj.net/video/20260122/eef5dc96-9ac0-4f4b-9944-c36951d47e40/1/hls/manifest-hd-wifi.m3u8

The Things That Clients Care Most About

Emily Green, head of wealth management at Ellevest, says advisors should “show up” where women are, be sensitive about how they are showing up, and focus on helping clients achieve their goals.

https://m.wsj.net/video/20260122/33e77af3-1032-4891-9284-c455d900f9d2/1/hls/manifest-hd-wifi.m3u8

Three Effective Ways for Advisors to Reach More Women

Ellevest’s head of wealth management discusses how the firm is addressing the gender wealth gap and how its advisors are helping female clients with all aspects of financial planning.

https://m.wsj.net/video/20260122/7bcfe251-9b72-47e7-b6d2-46b70f68b77c/1/hls/manifest-hd-wifi.m3u8

Emily Green: Women, Investing, and the Great Wealth Transfer

The Ameriprise Financial Services private wealth advisor discusses the centrality of the advisor-client relationship, the shift to holistic planning, and reasons why the financial planning process should be simplified.

https://m.wsj.net/video/20251216/0763524d-fc27-4495-a779-bbb533e16abc/1/hls/manifest-hd-wifi.m3u8

Doug Messina: The Importance of Strong Client Relationships

In terms of business continuity, “We don't leave until the client says, ‘yeah, I'm comfortable with so and so now and I know how to reach you if I need you,’” says Doug Messina, private wealth advisor with Ameriprise Financial Services.

https://m.wsj.net/video/20251216/32c51a2b-7ac0-4867-a758-7dd04ed104a1/1/hls/manifest-hd-wifi.m3u8

Transitioning Clients to a New Financial Advisor

“If you’re only hyper-focused on what’s happening in the market, it’s not going to do a whole heck of a lot,” says Doug Messina, private wealth advisor with Ameriprise Financial Services.

https://m.wsj.net/video/20251216/d08e7cf8-15b2-4d7b-b911-be1fa6058a65/1/hls/manifest-hd-wifi.m3u8

‘You Have to Be Able to Connect With People’

Be honest, be yourself, and “put yourself in the client’s position,” says Doug Messina, private wealth advisor with Ameriprise Financial Services.

https://m.wsj.net/video/20251216/e3bd3c54-c3c9-4856-b27b-52e1f20f96b3/1/hls/manifest-hd-wifi.m3u8

3 Pieces of Advice for Younger Advisors

Advisors need to “invest in the younger folks,” says Merrill Lynch private wealth advisor Tony Carpentieri, who asserts that developing “energetic, new, up and coming, and emerging players is the most important part” of succession planning.

https://m.wsj.net/video/20251204/b5efe5ba-edf5-4dc7-9040-2739b43dd9c4/1/hls/manifest-hd-wifi.m3u8

The ‘Most Important’ Part of Succession Planning Today

Barron's Advisor Next Generation

Will Nvidia and other technology companies keep powering the stock market in 2026? We'll speak with two veteran money managers about their views on tech and their favorite stocks for the coming year.

https://m.wsj.net/video/20251212/5683d7a0-ed1f-4e3c-b913-bb3367ea3abd/1/hls/manifest-hd-wifi.m3u8

Finding Bargains in a Pricey Market

Explore what could go right for investors, and what could go wrong, in a year that will see the AI trade evolve, the Fed's leadership change, and global competition for resources increase in this 2026 Outlook.

https://m.wsj.net/video/20251212/573f5954-c4ab-43e9-804d-f1ea93fbb70c/1/hls/manifest-hd-wifi.m3u8

Meeting the Challenge

Stocks are expensive, risks abound, and AI is about to change the world. Other than that, building a calamity-proof retirement portfolio should be a cinch. Tune in as two veteran money managers size up the markets and share their investment ideas.

https://m.wsj.net/video/20250211/17a5e7d6-7c36-44b0-a35e-bf5ac3a24194/1/hls/manifest-hd-wifi.m3u8

Saving for a Sunny Day

Research shows that people greatly underestimate the healthcare costs they’ll face in retirement. Learn from experts how to estimate those costs, prepare for potential long-term care needs, and manage healthcare expenses in retirement.

https://m.wsj.net/video/20250211/e7c022d9-badf-4e95-8e7c-0b6fce9f7823/1/hls/manifest-hd-wifi.m3u8

Are You Fiscally Fit?

Surging power demand, new energy sources, and growing competition have spurred the utility industry to become more innovative than ever before. Our panelists will unpack the changes afoot and explore what lies ahead for companies, customers, and investors.

https://m.wsj.net/video/20240917/001ea098-1fcc-4da5-9f0e-a3b149bbb2fb/1/hls/manifest-hd-wifi.m3u8

Not Your Father's Utility

Modernizing America's grid will take creativity and money -- lots of money. Learn how players across the power sector can achieve their electrification goals and serve new customers without breaking the bank for consumers.

https://m.wsj.net/video/20240917/bd6bd43a-bb07-4b7f-9d1c-6ae04220bea9/1/hls/manifest-hd-wifi.m3u8

Ready for a Revamp?

The launch this year of Bitcoin ETFs has made it easier for investors to buy and trade the cryptocurrency. But is that a wise move, and if so, how much crypto should you own?

https://m.wsj.net/video/20240529/cbb77f15-ef70-445d-85ae-5f02c24ea1ef/1/hls/manifest-hd-wifi.m3u8

Investing in Cryptocurrencies

Bitcoin and other digital currencies reside on software networks that aim to revolutionize everything from finance to art. Barron's talks to industry experts about the outlook for blockchain technology and its potential uses.

https://m.wsj.net/video/20240529/8f60a5ea-6de4-4c3c-b7c2-12b11aaa99f3/1/hls/manifest-hd-wifi.m3u8

Is Crypto Really a Game-Changer?

Persistent inflation means retirement savings don't go as far as they once did. We discuss the best inflation hedges, and how retirees can benefit from higher-for-longer interest rates.

https://m.wsj.net/video/20240429/69577ad6-cbaf-4d34-96f1-c42136e26aa2/1/hls/manifest-hd-wifi.m3u8

Protecting Your Nest Egg from Rising Prices

Barron's Roundtable

Whether you're leading a transition, building a scalable team, or just trying to stay ahead of the curve, this episode will give you practical insights to lead smarter and grow stronger.

https://m.wsj.net/video/20251010/fd26d60b-d1e6-409b-b51b-101da4aaa368/1/hls/manifest-hd-wifi.m3u8

Next-Gen Leadership Meets Smart Innovation

Electric vehicles sales are growing but not at the pace some expected. Some would-be buyers worry about the range of EV charging, and others are swayed by politics. But innovators from Detroit to Silicon Valley still envision a dramatic shift in how we get around. What’s going on and what’s next?

https://m.wsj.net/video/20240603/5784fa60-791c-47ad-9740-42e4553de5c4/1/hls/manifest-hd-wifi.m3u8

Forces Shaping EV Adoption and the Future of Driving

Success in improving the power grid to accommodate the electricity demands of the future will be a boon for companies doing the work and utilities that succeed. Explore the investing risks and opportunities.

https://m.wsj.net/video/20240522/2b825c69-2687-4d88-923b-0c8f523a2f67/1/hls/manifest-hd-wifi.m3u8

How to Invest in Initiatives to Bolster the Power Grid

Joanna Rotenberg, Fidelity's president of personal investing, discusses ways to make investing more accessible and how to bolster your own financial security.

https://m.wsj.net/video/20231025/8ad733df-ac90-41fd-9655-7761b3e0532c/2/hls/manifest-hd-wifi.m3u8

Mind the Gap: Demystifying Investing

Reshma Kapadia sits down with Cozy Wittman of College Inside Track to discuss how to tackle all things college, from what admission officers are seeking today, to navigating the different ways to funding higher education and evaluating the ROIs.

https://m.wsj.net/video/20230515/b7229011-05cc-42ec-9c16-1d7752ec668d/1/hls/manifest-hd-wifi.m3u8

Decoding the College Search and Financing Puzzle

Nicole Webb, financial advisor and SVP at Wealth Enhancement Group, shares ways to navigate the real estate market this spring whether you are a first-time buyer, a retiree downsizing or someone who is relocating or looking for a second home.

https://m.wsj.net/video/20230424/93eb00e1-caf0-4e83-9fc7-b502a57dc546/1/hls/manifest-hd-wifi.m3u8

Pro Tips on Buying and Selling a Home

Reggie Fils-Aimé, former president and COO of Nintendo of America, joins Barron's deputy editor Alex Eule to discuss his unlikely rise to the top, and the risks he took once there to beat the odds and achieve success.

https://m.wsj.net/video/20220630/61e2296d-ab1a-4216-ae65-24676447c616/1/hls/manifest-hd-wifi.m3u8

How Nintendo's Former President Disrupted the Gaming Industry

2050 Wealth Planners co-CEO Lazetta Rainey Braxton, Sequoia Financial Planners vice president Elizabeth Scheiderer, and MoneyZen founder Manisha Thakor offer tips on how to prepare for recession, inflation, caregiving needs.

https://m.wsj.net/video/20220617/a71025ce-518b-49b9-b098-21417863f8ce/1/hls/manifest-hd-wifi.m3u8

Financial Advice for the Inflation-Weary

Families and advisors have a lot to navigate when it comes to generational wealth transfer. Add sustainable investing to the list. Examine strategies to help close the generational divide. From the Dow Jones Energy & Sustainability event series.

https://m.wsj.net/video/20230210/85cbf3f9-b5ab-4bfa-93c6-f8e8a247d386/1/hls/manifest-hd-wifi.m3u8

Sustainable Investing and the Wealth Transfer

Barron's Events

Level Up

Barron's Explains

Back to Business

Great Investors

MarketWatch

Video Center - Barron's home

What began as a simple text to prove you aren’t a robot has rapidly evolved into a battle between humans and AI. WSJ explores the latest Captcha technology, and why AI algorithms may always get the upper hand. Photo Illustration: George Downs/The Wall Street Journal

https://m.wsj.net/video/20241112/6f657596-a810-4a05-82bb-7956b13aa0c9/2/hls/manifest-hd-wifi.m3u8

What began as a simple text to prove you aren’t a robot has rapidly evolved into a battle between humans and AI. WSJ explores the latest Captcha technology, and why AI algorithms may always get the upper hand.

The Battle Between Captcha and AI Is Heating Up | WSJ Tech Behind

Narrator: It's not just you, Captcha the online test to tell whether you're a human or a robot has been getting harder. This is one of the guys who invented it.

Oh yeah, I fail them all the time. I never know how much to say there's a traffic light if it's only like a tiny little corner of it.

Narrator: The problem is that Captcha was designed to keep malicious bots out of certain websites, but every time you've solved a task, you've actually made those bots smarter.

As more and more data was fed into these perceptual systems, they simply got a lot better at solving the perceptual tasks.

Narrator: So what does it take to design a puzzle that can outsmart a bot but still be solved by any human? This is The Tech Behind Captcha. So Captcha was first used around the same time that Yahoo began giving out free email addresses.

This was the year 2000. There were people who were writing programs to abuse different web services and there was no easy way to stop them. And the idea was there should be a test that is really quick that humans can pass, but computers could not.

Narrator: Luis's test looked like this, a string of letters slightly warped and distorted, that the end user had to input into a text field. He called it Captcha, which stands for completely automated public turing test to tell computers and humans apart. And he took advantage of the fact that computers at the time weren't very good at something called OCR, optical character recognition. The way it works is a simple game of pairs. The program scans the image and compares any shapes that emerge like this letter P against a database of different letters in different fonts. The second it finds a match, it has identified the letter. But if that P was warped, overlapping another letter, or had marks through it, then the program will struggle to find anything in its database that matches and won't be able to identify the letter. Simple, but enough to keep out the malicious bots.

The technology behind them was relatively primitive when it came to having access to what a letter looked like.

Narrator: But that advantage wouldn't last long. Here's Luis from 2010.

Is there some way in which we can use those 10 seconds while you're typing a Captcha for something that's useful?

Narrator: In 2007, reCaptcha was launched, an updated version that also helped to scan books. At the time, groups like the New York Times and the Internet Archive were in the process of trying to digitize old literature. Since optical character recognition wasn't very accurate at the time, the digitization had errors. So to try and help resolve those errors, reCaptcha began showing two words from a scanned document. One was a control word, a word the computer knew, but the other was a word it couldn't quite identify. In answering the Captcha, half of your answer was being used to pass the test, but the other half was used to tell the computer what word it was looking at, helping to improve OCR.

Not only are you authenticating yourself as a human, but in addition, you're helping to digitize books and newspapers.

Narrator: The technology was so efficient that Google acquired it in 2009, but a new problem emerged because Captchas relied on machines being bad at reading and we just taught them to be very good at it. Eventually the bots were able to get Captchas right frequently than humans. The test needed to evolve. So in 2012, Google deployed this, image-based Captcha.

There was a switch to go from distorted characters to the harder problem of distinguishing certain things in images where you have to pick all the ones that have a traffic light or a bicycle or whatever.

Narrator: Interestingly, when it comes to boxes like this where it's not exactly clear if this counts as a traffic light or not, there isn't actually a right or wrong answer.

The way to get it right is just what the majority of the human population says.

Narrator: But for machines, this was a huge new challenge. After all, they'd only just learned how to read. See, with text-based Captchas, the machines only had to identify a limited range of variables, letters, and numbers from a black and white background. But now with image Captchas, they had to be able to identify anything and spot an object in a very busy background. However, computer vision was just around the corner,

Whereas you and I would process the stream of perceptual input, the computer vision system is basically taking the pixels and processes strings of pixels, vectorized, we would say. And as it processes these images, it's picking up patterns in the images. It's picking up patterns in the pixels.

Narrator: Now, for any computer vision system to perform well, it needs a lot of labeled data.

It's being trained to identify cars by having many, many, many images of cars.

Narrator: The problem was that image-based Captcha was essentially a data labeling task. By solving it, you were once again generating data that could help a bot defeat it.

The systems just kept getting better and better 'cause they kept getting bigger and bigger.

Narrator: new approach was needed. So in 2014, Google launched the noCaptcha, one simple box. But this version of Captcha wasn't looking at whether you clicked the box. It was looking at how you clicked it and how you interacted with the rest of the internet. See, if you write code to make an object move to a certain point like a cursor, the simplest version will make it move in a straight line at a constant speed like a robot, but humans naturally aren't that accurate. We overshoot, we don't move in a perfectly straight line, and that is what this version of Captcha was looking for, human flaws. It was also monitoring things like your internet history and your typing speed. If the history was just a string of repeated attacks on the same website, you're probably a bot. But if you stopped halfway through the day to browse for shoes or look at cat videos, you might just be human. By 2018, Google had done away with the tick box entirely and launched reCaptcha V3, based solely on that hidden data. But even flawed human characteristics is something that a smart algorithm can eventually learn to mimic. So are the bots always destined to win? Well, perhaps. See, despite other companies coming up with new and inventive tests, there's a quirk at the very heart of Captcha that means it's likely the bots will always be able to win eventually. And to understand why you need to go back to before the internet was invented to the man who Captcha is named after, Alan Turing. He's considered one of the founding fathers of AI after he penned this paper, "Computing Machinery and Intelligence". In it, he describes a method to test whether you're talking to a human or a machine.

You had a questioner right behind the screen and trying to differentiate between a human and a computer machine giving answers. This now has famously become known as the turing test.

Narrator: The problem with Captcha is that the questioner isn't human, it's a computer. And therefore any information that's input into the computer has the potential to be used by AI models to train Captcha-defeating bots. Even Luis's original paper on Captchas says that the technology will act as a security measure for websites and advance the field of AI.

You have the research world almost continually catching up and surpassing the Captcha world.

Narrator: But the solution may be to take the test outta the computer and into the real world.

We all have mobile phones and they have so many different sensors within them, being able to tilt the phone on instruction or being able to take a few steps in one direction or another using the sensors in the phone.

Narrator: But in order for us to truly prove that we're human online, we may have to find an entirely new approach.

I think the question now is not are we doomed? It's how do we seize control again?

I would not be designing a Captcha today. I think that's a losing battle. It's too hard.