"It is dangerous to make predictions about where tech is going," John Oliver said on Sunday's Last Week Tonight, citing the deflated excitement over Google Glass. That was his caveat in discussing cryptocurrencies, or "everything you don't understand about money combined with everything you don't understand about computers." Even though bitcoin's value has plummeted by nearly half from its astronomical valuation at the end of 2017, "there is still a cryptocurrency fervor going on," he said. "So with all this excitement and curiosity, we thought we'd try and explain a few things tonight," Oliver said: "Bitcoin, blockchain — the technology that allows it to exist — and cryptocurrencies in general." Like any currency, bitcoin has value because people believe it has value, but there are still some kinks to work out.