[MUSIC] What is blockchain? Blockchain is a network of computers that polices itself, so people or businesses can cooperate without fear that somebody is tampering with the data. Today most data is sealed up at a central organization, like a bank or the Department of Motor Vehicles. Watching moves that information to a decentralized shared network [UNKNOWN] theaters maybe even thousands of them. To create an open transparent and mutable database. That data can include everything from sales transactions to medical records. It's called the block chain because computers periodically collect transactions into group called blocks. Each block gets a digital fingerprint called a hash And each new block's hash is cryptographically linked to the previous block's hash, basically forming an unbreakable chain. Any tampering with a transaction is easily detected and rejected because it messes up the hash, not only of the block it's in, but also every other block added afterward. If a tampered block is on your computer, the rest of the blockchain just ignores it. In the future for instance, there maybe a blockchain network for concert ticket sales. You want to buy a ticket from a stranger, somebody you might not trust in the real world. The blockchain takes care of confirming that the original owners legitimate hasn't sold the ticket already and that you're the new owner. Then the network blocks the data. [MUSIC] Many companies are investing in blockchain and many more are investigating Walmart is testing blockchain so it can quickly pull contaminated food from store shelves and [UNKNOWN] as tracking diamonds. So you can be sure those anniversary earings didn't fund somebody's war. You might not notice blockchain as it makes businesses run more smoothly. But more directly, it should bring you peace of mind. [BLANK_AUDIO]