Usage for hash tag: ExplainCopenhagen

...minh là gì?] (Https://www.investopedia.com/terms/s/smart-contract.asp) ======================================= #BlockChain #xkcd #ExplainCopenhagen** [Image of the XKCD comic "Explain Copenhagen"](https://imgs.xkcd.com/comics/explain_copenhagen.png) The XKCD comic "Explain Copenhagen" is a...