Block chain meaning is a digital ever-growing list of data records. This list is composed of many blocks of data, which are organised in chronological order and are linked and secured by cryptographic proofs.
The inaugural trace of a blockchain can be found in the early 1990s. Computer scientist Stuart Haber and physicist W. Scott Stornetta applied cryptographic techniques in a chain of blocks as a way to secure digital documents from data tampering. This then inspired the work of Dave Bayer, Hal Finney and many other computer scientists to create Bitcoin, the first cryptocurrency.
Blockchain is a core fundamental component of most cryptocurrency networks, acting as a decentralized, distributed and public digital ledger that is capable of keeping a permanent record of all previously confirmed transactions. Additionally, because blockchain transactions occur within a peer-to-peer platform of nodes, each node can maintain a copy of the blockchain and contribute to the functionality and security of the network. This is what enables Bitcoin to be a decentralized digital currency that does not require any central authority or third-party intermediary.
Blockchains are intentionally designed to be highly resistant to modification and frauds (such as double-spending). This is true because the Bitcoin blockchain, as a database of records, cannot be mutated, nor can it be tampered without an impractical amount of electricity and computational power. This is what we call Proof of Work, which is a consensus mechanism that gives miners with strong computational power the right to make changes to the blockchain.
Blockchains do not only have uses in cryptocurrencies, as such a technology can also be adapted and implemented in other areas like healthcare, IOT etc.
In conclusion, block chain meaning is a digital ever-growing list of data that is cryptographically secured and stored in a database.
