Blockchain technology is most simply defined as a decentralized, distributed ledger that records the provenance of a digital asset.
From Wikipedia:
A blockchain,[1][2][3] originally block chain,[4][5] is a growing list of records, called blocks, that are linked using cryptography.[1][6] Each block contains a cryptographic hash of the previous block,[6] a timestamp, and transaction data (generally represented as a Merkle tree).
Key Points:
A blockchain is a digital record of transactions. The name comes from its structure, in which individual records, called blocks, are linked together in single list, called a chain. Blockchains are used for recording transactions made with cryptocurrencies, such as Bitcoin, and have many other applications.
Blockchain is a better, safer way to record activity and keep data fresh, while maintaining a record of its history. The data can’t be corrupted by anyone or accidentally deleted, and you benefit from both a historical trail of data, plus an instantly up-to-date record.
Blockchains are a fascinating new technology. They enable fully decentralized databases, resistant to censorship and potentially allowing for system adoption in critical applications like money and identity.
Blockchain in the future will revolutionize business processes in many industries, but its adoption requires time and efforts. Nevertheless, in the near future, we can expect that governments will finally accept blockchain benefits and begin to use it for improving financial and public services.
The main thing distinguishing a blockchain from a normal database is that there are specific rules about how to put data into the database. Finally, everyone agrees on what the state of the things in the database are (canonical) without a central party (decentralized).
The application of Blockchain technology is not limited only to the finance industry. It has a fantastic future in different sectors such as supply chain management, digital advertising, forecasting, cyber security, Internet of things, networking, etc.