Why do websites require CAPTCHA?
Show answer & explanation
Answer: Distinguish humans from bots
Distinguish humans from bots ✓ — Correct! CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) blocks bots from: creating fake accounts, scraping data, spamming, ticket scalping, brute-force login attempts. Challenges exploit tasks hard for computers: distorted text recognition, image categorization ('select traffic lights'), behavior analysis (reCAPTCHA tracks mouse movement). AI improvements require harder CAPTCHAs—ongoing arms race!
Collect user data — Wrong. Some CAPTCHAs (reCAPTCHA) train AI with image labeling, but primary goal is bot detection to prevent abuse.
Slow down website traffic — Wrong. CAPTCHAs don't slow traffic—they prevent automated bot abuse like spam, scraping, and fake account creation while letting humans through.
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