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Captcha vs Null - What's the difference?

captcha | null |

As nouns the difference between captcha and null

is that captcha is (captcha) while null is zero, nil; the cardinal number before einn.

captcha

English

Noun

(en noun)
  • A CAPTCHA is a human response test that requires you to enter a series of letters and/or numbers and/or symbols correctly to prove you are a human and not a computer program attempting to spam the site.
  • (by extension) Anything that a human must do to prove that they are not a computer.
  • Derived terms

    * audio CAPTCHA, a distorted audio file containing a voice reading numbers. * visual CAPTCHA, when a distinction must be made between an audio CAPTCHA and a distorted image.

    Usage notes

    Although occasionally spelt with lowercase letters (captcha), or with an initial uppercase letter (Captcha), most authors remain aware of its origin as an acronym and use uppercase. abandoned their attempt to trademark this term in 2008, as usage was already too widespread. (USPTO file number 78500434).

    See also

    * Turing test * ("CAPTCHA" on Wikipedia) English eponyms

    null

    English

    Noun

    (en noun)
  • A non-existent or empty value or set of values.
  • Zero]] quantity of [[expression, expressions; nothing.
  • (Francis Bacon)
  • Something that has no force or meaning.
  • (computing) the ASCII or Unicode character (), represented by a zero value, that indicates no character and is sometimes used as a string terminator.
  • (computing) the attribute of an entity that has no valid value.
  • Since no date of birth was entered for the patient, his age is null .
  • One of the beads in nulled work.
  • (statistics) null hypothesis
  • Adjective

    (en adjective)
  • Having no validity, "null and void"
  • insignificant
  • * 1924 , Marcel Proust, Within a Budding Grove :
  • In proportion as we descend the social scale our snobbishness fastens on to mere nothings which are perhaps no more null than the distinctions observed by the aristocracy, but, being more obscure, more peculiar to the individual, take us more by surprise.
  • absent or non-existent
  • (mathematics) of the null set
  • (mathematics) of or comprising a value of precisely zero
  • (genetics, of a mutation) causing a complete loss of gene function, amorphic.
  • Derived terms

    * nullity

    Verb

    (en verb)
  • to nullify; to annul
  • (Milton)

    See also

    * nil ----