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Hub AI
CAPTCHA AI simulator
(@CAPTCHA_simulator)
Hub AI
CAPTCHA AI simulator
(@CAPTCHA_simulator)
CAPTCHA
A CAPTCHA (/ˈkæp.tʃə/ KAP-chə) is a type of challenge–response Turing test used in computing to determine whether the user is human in order to deter bot attacks and spam.
The term was coined in 2003 by Luis von Ahn, Manuel Blum, Nicholas J. Hopper, and John Langford. It is an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart." A historically common type of CAPTCHA (displayed as reCAPTCHA v1) was first invented in 1997 by two groups working in parallel. This form of CAPTCHA requires entering a sequence of letters or numbers from a distorted image. Because the test is administered by a computer, in contrast to the standard Turing test that is administered by a human, CAPTCHAs are sometimes described as reverse Turing tests.
Two widely used CAPTCHA services are Google's reCAPTCHA and the independent hCaptcha. It takes the average person approximately 10 seconds to solve a typical CAPTCHA. With the rising application of AI making it feasible to defeat the tests and the appearance of scams disguised as CAPTCHAs, their use risks being outmoded.
The purpose of CAPTCHAs is to prevent spam on websites, such as promotion spam, registration spam, and data scraping. Many websites use CAPTCHA effectively to prevent bot raiding. CAPTCHAs are designed so that humans can complete them, while most robots cannot. Newer CAPTCHAs look at the user's behaviour on the internet, to prove that they are a human. A normal CAPTCHA test only appears if the user acts like a bot, such as when they request webpages, or click links too fast.
Since the 1980s–1990s, users have wanted to make text illegible to computers. The first such people were hackers, posting about sensitive topics to Internet forums they thought were being automatically monitored on keywords. To circumvent such filters, they replaced a word with look-alike characters. HELLO could become |-|3|_|_() or )-(3££0, and others, such that a filter could not detect all of them. This later became known as leetspeak.
One of the earliest commercial uses of CAPTCHAs was in the Gausebeck–Levchin test. In 2000, idrive.com began to protect its signup page with a CAPTCHA and prepared to file a patent. In 2001, PayPal used such tests as part of a fraud prevention strategy in which they asked humans to "retype distorted text that programs have difficulty recognizing." PayPal co founder and CTO Max Levchin helped commercialize this use.
A popular deployment of CAPTCHA technology, reCAPTCHA, was acquired by Google in 2009. In addition to preventing bot fraud for its users, Google used reCAPTCHA and CAPTCHA technology to digitize the archives of The New York Times and books from Google Books in 2011.
CAPTCHAs are automated, requiring little human maintenance or intervention to administer, producing benefits in cost and reliability.
CAPTCHA
A CAPTCHA (/ˈkæp.tʃə/ KAP-chə) is a type of challenge–response Turing test used in computing to determine whether the user is human in order to deter bot attacks and spam.
The term was coined in 2003 by Luis von Ahn, Manuel Blum, Nicholas J. Hopper, and John Langford. It is an acronym for "Completely Automated Public Turing test to tell Computers and Humans Apart." A historically common type of CAPTCHA (displayed as reCAPTCHA v1) was first invented in 1997 by two groups working in parallel. This form of CAPTCHA requires entering a sequence of letters or numbers from a distorted image. Because the test is administered by a computer, in contrast to the standard Turing test that is administered by a human, CAPTCHAs are sometimes described as reverse Turing tests.
Two widely used CAPTCHA services are Google's reCAPTCHA and the independent hCaptcha. It takes the average person approximately 10 seconds to solve a typical CAPTCHA. With the rising application of AI making it feasible to defeat the tests and the appearance of scams disguised as CAPTCHAs, their use risks being outmoded.
The purpose of CAPTCHAs is to prevent spam on websites, such as promotion spam, registration spam, and data scraping. Many websites use CAPTCHA effectively to prevent bot raiding. CAPTCHAs are designed so that humans can complete them, while most robots cannot. Newer CAPTCHAs look at the user's behaviour on the internet, to prove that they are a human. A normal CAPTCHA test only appears if the user acts like a bot, such as when they request webpages, or click links too fast.
Since the 1980s–1990s, users have wanted to make text illegible to computers. The first such people were hackers, posting about sensitive topics to Internet forums they thought were being automatically monitored on keywords. To circumvent such filters, they replaced a word with look-alike characters. HELLO could become |-|3|_|_() or )-(3££0, and others, such that a filter could not detect all of them. This later became known as leetspeak.
One of the earliest commercial uses of CAPTCHAs was in the Gausebeck–Levchin test. In 2000, idrive.com began to protect its signup page with a CAPTCHA and prepared to file a patent. In 2001, PayPal used such tests as part of a fraud prevention strategy in which they asked humans to "retype distorted text that programs have difficulty recognizing." PayPal co founder and CTO Max Levchin helped commercialize this use.
A popular deployment of CAPTCHA technology, reCAPTCHA, was acquired by Google in 2009. In addition to preventing bot fraud for its users, Google used reCAPTCHA and CAPTCHA technology to digitize the archives of The New York Times and books from Google Books in 2011.
CAPTCHAs are automated, requiring little human maintenance or intervention to administer, producing benefits in cost and reliability.