Central banks are looking at creating their own digital currencies - a stark contrast to the ethos of cryptocurrencies that seek to subvert mainstream authority over money.
While there is little consensus on how such currencies might take off, some countries such as the United States and European nations are looking at the concept, while China is the global frontrunner in a drive to make its own digitised money.
The European Union - worried that Facebook's Libra cryptocurrency could erode state control over fiat money - has urged the European Central Bank to look at issuing a digital currency, a draft document seen by the Reuters news agency shows.
Here are some key questions on the rise of central bank digital currencies (CBDCs) and their progress in entering the mainstream:
Are CBDCs different from cryptocurrencies?
Yes - and fundamentally so.
CBDCs are traditional money, but in digital form - issued and governed by a country's central bank. By contrast, cryptocurrencies such as bitcoin are produced (or mined) by solving complex mathematics puzzles and are governed by disparate online communities instead of a centralised body.
The common denominator is that cryptocurrencies and CBDCs, to a varying degree, are based on blockchain technology, a digital ledger that allows transactions to be recorded and accessed in real-time by multiple parties.
While some retailers accept bitcoin as a form of payment, cryptocurrencies are not recognised as legal tender - which CBDCs, by definition, would be.
And unlike the value of central bank money, traditional and digital, the value of cryptocurrencies is determined entirely by the market, and not influenced by factors such as monetary policy or trade surpluses.
What about electronic cash?
The rise of technologies such as contactless debit cards has made it easier for consumers and businesses to use electronic cash, or e-money, to pay for goods and services.
But this also differs from CBDCs.
Electronic cash, defined by the Bank for International Settlements as a store of value for making payments to retailers or between devices, is usually held at banks, on pre-paid cards or in digital wallets such as PayPal.
CBDCs would not merely be a representation of minted physical money, as is the case with electronic cash - but a complete replacement for notes and coins.
What are the advantages of CBDCs?
Central banks think CBDCs could make payment systems - often time-consuming and costly - more efficient by reducing transfer and settlement times and thus stoking economic growth.
Some central banks think CBDCs could also counter the rise of cryptocurrencies issued by the private sector such as Facebook's Libra, planned for launch in June 2020.
Bitcoin and other virtual currencies, hampered by the wild volatility, have presented few realistic threats to central banks' control over money. But central bankers fret that Libra could reach billions and could quickly erode sovereignty over monetary policy.
CBDCs, they think, could address problems like inefficient payments that cryptocurrencies seek to solve while maintaining state monopolies over currency.
In the era of negative interest rates, CBDCs are also seen as offering a tool to control how businesses and people use money. CBDCs, the argument goes, could be used to charge households and businesses to hold cash, forcing them to spend and invest.
Are CBDCs close to becoming a reality?
Increasingly so, though most CBDCs are still in the very early or conceptual stages.
While central banks across the world have in recent years researched the concept, China is closest to becoming the first major country to introduce a CBDC.
While details of China's project to build a digital renminbi are scarce, the effort will be powered in part by blockchain technology. And the digital yuan will initially be issued to commercial banks and other financial institutions.
China's move may push other central banks to take action.
The president of the US Federal Reserve Bank of Philadelphia said last month it was "inevitable" that central banks, including the US Federal Reserve, would start issuing their own digital currencies.
Are most major central banks supportive?
Caution and scepticism exist in many quarters. The Bank of Japan (BOJ), for example, has warned that uncertainties over the effect of CBDCs on commercial banking must be addressed.
The BOJ has also scotched the idea that CBDCs could boost the effectiveness of negative interest rate policies.
Some households and companies, it thinks, would hoard traditional cash to avoid being charged for holding digital currencies, if central banks were to issue and apply negative rates on them.