NBD is the acronym for the phrase “No Big Deal” usually stated when something, in fact was a big deal.
It may also carry other connotations, such as “Next Business Day” or “Never Been Done” though these are not as commonly used, since they are fitting in only in certain contexts.
Like most internet abbreviations, it originates from the early 2000’s, the first Urban Dictionary entry on it being added at 2004.
The first actual definition of the actual meaning was added a year later, with several others explaining the meaning behind this acronym with rather ingenious and hilarious examples being used.
Nbd is used mostly in text messaging, facilitating the lives of many, who have big, sausage like Shrek fingers and saving time in this busy and occupied world, where every moment is precious.