What do you think about cryptocurrencies and mollars?

Cryptocurrencies are digital assets, which since their beginnings in mid-2008 with the well-known pioneer (Bitcoin). Have transformed part of commerce, having a terrifying boom for some and beneficial for others, these cryptographic assets have become those loved by many and repudiated by those who claim that all this is just a bubble which is preparing to explode in the least expected moment, and in this way make all those investors lose billions... What do you think about cryptocurrencies?