It means exactly the same as bitcoins. You have an entry on some computers somewhere. The difference is that the entry on a regulated bank's computer can be us

It means exactly the same as bitcoins. You have an entry on some computers somewhere. The difference is that the entry on a regulated bank's computer can be used to settle a tax bill, or a loan. The entry in a blockchain can do neither. So at some point you have get the right sort of money to settle debts imposed on you by wider society. Blockchain 'currencies' are just intangible bottles of wine, artworks, or tulip bulbs and will go through the same bubble and bust as all those things have previously.