Blockchain

Blockchain is a system of recording information in a way that makes it difficult or impossible to change, hack, or cheat the system. A blockchain is essentially a digital ledger of transactions that is duplicated and distributed across the entire network of computer systems on the blockchain.
The blockchain network has no central authority—it is the very definition of a democratized system. Since it is a shared and immutable ledger, the information in it is open for anyone and everyone to see. Hence, anything that is built on the blockchain is by its very nature transparent and everyone involved is accountable for their actions.
Each transaction made on the blockchain network exercises one “block”—each block stores information about the parties involved in the transaction, the date and time of the transaction, the amount transferred, etc. The important thing to note here is that all this data exists at each node (computer connected to blockchain) in the network, so they all store identical data in real-time – this means there are thousands of copies of identical blocks in existence at any moment in time.

Bitcoin and Ethereum are the most popular examples of blockchains. They are a network of computers that all connect to the same ledger. Anyone with an internet connection is allowed to download the blockchain software and connect with the network. Once they’ve done that, they can begin transacting on the blockchain.

A blockchain is a way of storing information, one that makes it impossible for people to change. This means you can trust the information because you know it hasn’t been changed since it was first written into the blockchain.