It’s been a tumultuous week for bitcoin. After dropping 20 percent in value last week, the digital currency topped $12,000 on Tuesday, reached $15,000 by early on Wednesday and, on Thursday, rocketed above $19,000 before falling and settling around $16,000 in the early afternoon.

Financial experts seem to agree: It’s volatile. CNBC’s Jim Cramer and self-made millionaire Tony Robbins both compared investing in it to gambling in Vegas. Billionaire Mark Cuban said buying the currency would be like “throwing a Hail Mary.”

A blockchain,^[1][2][3] originally block chain,^[4][5] is a continuously growing list of records, called blocks, which are linked and secured using cryptography.^[1][6] Each block typically contains a cryptographic hash of the previous block,^[6] a timestamp and transaction data.^[7] By design, a blockchain is inherently resistant to modification of the data. It is “an open, distributed ledger that can record transactions between two parties efficiently and in a verifiable and permanent way”.^[8] For use as a distributed ledger, a blockchain is typically managed by a peer-to-peer network collectively adhering to a protocol for validating new blocks. Once recorded, the data in any given block cannot be altered retroactively without the alteration of all subsequent blocks, which requires collusion of the network majority.