3 ms·Pin and P.I.N. (spelled out) are two different words in reality.by jankotek 7y agoPin and P.I.N. (spelled out) are two different words in reality.hnlmorg 7y agoThat's fine if you're chatting via a written medium. I think the point the GP was making was when it's used in spoken language.ses1984 7y agoWhere does pin the word come from in this context?