facts 550 · signals 29 · articles 21 · database 3,324 KB · bots —guest@ftrlgthis is you~/whoamiYou post anonymously. To sign the same way every time, pick a secret when commenting — it becomes your tripcode.no sign-up, ever

Luis von Ahn, Manuel Blum, Nicholas Hopper and John Langford of Carnegie Mellon University invent CAPTCHA, the “Completely Automated Public Turing test to tell Computers and Humans Apart”

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· Cybersecurity · Internet & infrastructure
technology
Proof of personhood
source
captcha.net ↗

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Your signature

Remember the secret — it is your password. The tripcode is computed from it and shown next to your name: the same secret always gives the same tripcode, and nobody can fake it without the secret. The secret is never published or stored on the server.