Blockchain is one of the major tech stories of the past decade. But beneath the surface chatter there’s not always a deep, clear understanding of what blockchain is, how it works, or what it’s for. Despite its reputation for impenetrability, the basic idea behind blockchain is pretty simple. And it has major potential to change industries from the bottom up.

Put simply, blockchain is a technology that enables the secure sharing of information. Data, obviously, is stored in a database. Transactions are recorded in an account book called a ledger. A blockchain is a type of distributed database or ledger, which means the power to update a blockchain is distributed between the nodes, or participants, of a public or private computer network. This is known as distributed ledger technology (DLT). Nodes are rewarded with digital tokens or currency to make updates to blockchains.

Blockchain allows for the permanent, immutable, and transparent recording of data and transactions. This, in turn, makes it possible to exchange anything that has value, whether that’s a physical item or something more intangible.

A blockchain has three central attributes:

• First, a blockchain database must be cryptographically secure. That means you need two cryptographic keys to access or add data on the database: a public key, which is basically the address in the database, and the private key, which is an individualized key that must be authenticated by the network.
• Next, a blockchain is a digital log or database of transactions, meaning it happens fully online.
• And finally, a blockchain is a database that is shared across a public or private network. One of the most well-known public blockchain networks is the Bitcoin blockchain. Anyone can open a Bitcoin wallet or become a node on the network. Other blockchains are private networks. These are more applicable to banking and fintech, where people need to know exactly who is participating, who has access to data, and who has a private key to the database. Other types of blockchains include consortium blockchains and hybrid blockchains, both of which combine different aspects of public and private blockchains.