As a society, we've developed institutions, like law firms and banks, to handle the exchange of property and money.
But many of these exchanges can also be achieved using blockchain technology as a smart contract — or a self-executing contract. Smart contracts use rules to require that one thing happens in order to get a desired outcome.
If Person A is leasing an apartment, for example, the smart contract could require that Person B transfer $1,000 to Person A in exchange for the apartment door code.
Blockchains eliminate the risk of having a middleman who defrauds someone on either side of the transaction or who takes the money and runs.