If you’ve been hearing or reading a lot about blockchain but you still aren’t entirely certain how to define it, you’re not alone. It’s something that Jack Dorsey, the chief executive officer and chairman of Square (and CEO of Twitter), describes as the “next big unlock,” something that, he notes, is normally applied to accounting terms but has the potential to “be applied to so much more.”

In an interview earlier this week at the Computer History Museum in Mountain View, California, I had the chance to ask Dorsey about Square’s business, the future of banking, cryptocurrencies, blockchain, and more.

Blockchain is often defined as a ledger that enables secure, encrypted transactions. Some financial and technical experts have described it as analogous to the early days of the internet: it’s a framework or backbone for transactions, while the various use cases for it are analogous to apps on the internet as we know them today.

But Dorsey also went beyond that interpretation of it, adding that the ability to “distribute and decentralize the ledger enables proof of work, and proof of one entity, in an untrusted network.” Even if there’s a hostile entity or a mistrust in the network, Dorsey said, “we can still account for value creation and the transfer of values as well.”

“There are so many problems we can help solve [with blockchain] that are not just related to finance, but finance is an obvious one,” he added.

“There are so many problems we can help solve that are not just related to finance.”

However, the availability of blockchain technology doesn’t necessarily mean that everyone should jump on the blockchain bandwagon. “I think there are going to be a bunch of people who say, ‘Blockchain, let’s go apply it everywhere’ and ‘Let’s try to solve every single problem with it,’” Dorsey said, “in the same way that we try to solve every problem with machine learning and data science and deep learning and artificial intelligence. And I think we need to be more thoughtful. What are people struggling with? How does the technology help them progress or does it distract them?”

Dorsey also spoke about bitcoin, which Square has accepted as a form of payment since the fall of 2014. Dorsey also admitted he has personally invested in Bitcoin, though he didn’t share how many bitcoins he holds.

He said one of the most surprising things he’s experienced recently is when friends and family, who aren’t as close to the technology industry, have been asking about bitcoin — specifically, how to invest in the cryptocurrency.

“I’m from St. Louis, Missouri, and I have a lot of friends and family who are not into technology,” Dorsey said. “Over the holidays, one of the things I kept getting asked by people I know is, ‘You work in technology, you work in finance, how do I buy bitcoin?’ I asked, ‘Why do you want to buy bitcoin?’ And they said, ‘Well I heard it’s a fast easy way to make money... someone said it’s like digital gold.’”

Dorsey went on to discuss the benefits of — and potential problems with — investing in a digital asset that is decentralized, deflationary, and in general, unlike any other traditional stock market securities. The full video is below. It’s a long discussion, but it’s a rare in-depth conversation with an entrepreneur who has firmly established himself as a disruptor in more than one industry.