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CAPTCHA - definition and synonyms

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90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

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  1. From our crowdsourced Open Dictionary
    an acronym which describes a program that protects websites from spammers by providing a test (e.g. a distorted text) which humans can do but computers cannot. It stands for 'Completely Automated Public Turing Test To Tell Computers and Humans Apart' and is a trademark of Carnegie Mellon University. There are visual as well as audio captchas in use.

    Recognising the kinds of characters used in CAPTCHAs remains a significant challenge in computer vision.

    Submitted on 28/09/2009
     

Open Dictionary

platform capitalism

a way of doing business that involves recruiting large numbers of people who work for themselves using the company's platform, as used by companies such as Uber, Deliveroo and the like

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