Yes, these are very very sweet memories in between sweet relations.
we read something on the page of a magazine and page number was 56 so we used to mention it in public place whenever required and it was a big fun for a long time.
we had lot of words which were secret, meaningful and funny as well...it is a big fun in between friends and any other relation. Every code has an interesting story behind it :)
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Yes, there were so many during school and college days. If I play the mouthorgan, my friend will come out of his hostel room and join me. There were specific codes like 'Nayar tea-stall' means 'go out for a movie', 'Lemon-rice' means the 'class is boring', 'samosa' means 'that girl is watching', 'raising the eyebrows' means 'the warden is coming' and so on....!