If you don't understand how to buy and sell bitcoin, you're not alone.

According to Jonathan Johnson, president of Medici Ventures and a board member of Overstock.com Inc. (OSTK) - Get Report , you could soon be buying that Starbucks Inc. (SBUX) - Get Report coffee using bitcoin instead of your debit card.

How does Johnson know?

"We see increased cryptocurrency purchases on the Overstock website," Johnson told TheStreet. "Crypto adoption is happening."

Overstock began accepting cryptocurrency for payment on its online site in 2014. The company has since pivoted hard to blockchain technology, creating subsidiary Medici Ventures as an incubator of sorts for blockchain-focused business ideas. To Johnson, bitcoin is going to become more than the currency of the technologically inclined few.

"Cryptocurrencies are going to be a way for people around the globe to participate in the global economy, particularly those that are currently unbanked," he added. According to the World Bank, about 38% of the world's population is without a bank account.

Adoption could happen faster overseas than it will in the U.S. because domestically the dollar is strong and stable and most Americans are banked. Only about 7% to 8% of the U.S. is unbanked.

In the Caribbean, that number rises to 40%. In South America, it's 70%. And in Africa, it's 90%.

Expanding financial inclusion to the far reaches of all seven continents is possible using blockchain. While about half the world's population still doesn't have reliable internet access, the figure is shrinking with each passing year. And it's more realistic to envision a future with global internet access than it is a future with a bank within walking distance of all people.

"A digital currency, whether it's a fiat currency or a cryptocurrency, is going to be a real life changer for people that don't have bank accounts," Johnson said.

Plus, digital currencies aren't subject to the political turmoil fiat currencies are. They're a universal store of value, not paper money susceptible to rampant inflation, over-printing or policy manipulation.

"Unlike government-issued fiat dollars, many of the cryptocurrencies, and bitcoin in particular, are capped at the number of coins that will ever be mined," Johnson said. "So they're not subject to continual inflation through central bank printing."

While inflation isn't a concern for bitcoin, the threat of a bubble might be.

As its price surges to nearly $20,000 per coin, many are calling bitcoin the next Tulipmania. Even if the bubble does pop, that's not a concern for Johnson.

"Not being a trader, but being a believer in the underlying technology and also what bitcoin is," Johnson said, "I don't spend any time thinking about when is it hitting top, when is it going to plunge. My view is long term it will have great value, so for me, I'm a buy-and-hold person."

For now, at least, Johnson and his Overstock team are sticking to their guns. People have begun to see the value in crypto, he said, and investing in Overstock has become a means of participating in the new market without as much risk.

To him, it's entirely possible a barrel of oil, for example, could in a decade be quoted in bitcoin instead of dollars.

"In the coming years, blockchain will affect everyone," Johnson said. "Even if they don't understand it."

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