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Which of the following to use, especially in the context of programming:

  • hashtag
  • well number
  • pound sign

marked as duplicate by Edwin Ashworth, JEL, k1eran, curiousdannii, Peter Shor Sep 4 '16 at 11:39

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  • 2
    Note: the character is sometimes known as hash. Hashtag is a phrase preceded by the hash symbol. – michael.hor257k Sep 4 '16 at 8:17
  • "Here, Octothorpe! Come here, boy!" – Hot Licks Sep 4 '16 at 12:42

In the context of programming I would call it by its Unicode name NUMBER SIGN.

  • Thanks, and what about in daily life? – Eric Wang Sep 4 '16 at 8:08
  • It depends on the context. As you can see from the link above, number sign is the preferred name - but I suppose hash might be more appropriate if you're discussing Twitter, for example. And of course it would be pound sign if it represents UK currency. – michael.hor257k Sep 4 '16 at 8:13
  • 2
    @michael.hor257k The UK currency pound sign is £. People in the UK would not assume that #10 meant 'ten pounds' without a lot of context to clue them into the writer's error. It is also not used to indicate pounds in weight, ie 10lbs. The symbol isn't generally used to indicate 'number' in the UK either; Nr and N° being more usual. Until hashtags happened most people experienced it as a key on touchtone phones 'please enter your PIN, followed by the hash key'. – Spagirl Sep 4 '16 at 8:38
  • The usage of # as pound sign refers to weight, not the British (and other nations') currency. It is very rarely used in this context anymore, but a "10# bag of potatoes" means it weighs 10 pounds (i.e., 4.5 kg), not that it costs £10. en.wikipedia.org/wiki/Number_sign#Usage_in_North_America – Mike Harris Dec 13 '17 at 20:29

I think it depends on the context you are in as the sign itself goes by many names - all of which are equally valid. I've even read a programming manual in which it was referred to by its formal name: octothorpe. See this article also.

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