File:Gimpy-r_CAPTCHA.jpg · Wikimedia Commons · See Wikimedia Commons
CAPTCHA
Sign in to saveAlso known as Completely Automated Public Turing test to tell Computers and Humans Apart, CAPTCHA (Challenge-response test)
upright=1.35|thumb|This CAPTCHA (GIMPY-R, c. 2005) of "smwm" obscures its message from computer interpretation by twisting the letters and adding a slight background color gradient.
A CAPTCHA is a test that asks you to prove you're human by completing a task a computer can't easily do, like reading distorted letters or identifying objects in images. Websites use CAPTCHAs to prevent automated programs from accessing accounts or abusing services.
AI-generated from the Wikipedia summary — may contain errors.
Wikidata facts
- Official website
- captcha.net
- Image
- Captcha.svg
Show 2 more facts
- Commons category
- Captcha
- inception
- 2000-01-01
Sources (2)
via Wikidata · CC0
~14 min read
Article
15 sectionsContents
- Purpose
- History
- Characteristics
- Accessibility
- Circumvention
- Machine learning–based attacks
- Human labor
- Outsourcing to paid services
- Insecure implementation
- Alternative CAPTCHAs
- Malicious CAPTCHA imitations
- See also
- References
- Further references
- External links
upright=1.35|thumb|This CAPTCHA (GIMPY-R, c. 2005) of "smwm" obscures its message from computer interpretation by twisting the letters and adding a slight background color gradient.
A CAPTCHA ( ) 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.