BlockChain- The Technology
The Blockchain is an encrypted, distributed database that records data. One of the key features of Blockchain is that this digital ledger is accessible across several hundreds and thousands of computer and is not bound to be kept in a single place. Blockchain chain has already started disrupting the financial services sector, and it is this technology which underpins the digital currency- Bitcoin transaction.
Satoshi Nakamoto is the name used by the presumed pseudonymous person or persons who developed bitcoin, authored the bitcoin white paper, and created and deployed bitcoin's original reference implementation. As part of the implementation, Nakamoto also devised the first blockchain database.
BlockChain Technology is used in Cryptocurrency, NFT (Non-fungible token), Healthcare, Smart Contracts and etc.
Every block, contains what is known as a Cryptographic Hash. It is analogous to Aadhar number, Social Security Number or any other unique idetification number, for us. This hash (for e.g. 4760RFLG07LDD492K8381O82P78C29QWMN02C1051B6624E99) is generated from the data within the block, and works as a digital signature for every single block. Also every single block contains the hash of the block preceeding it as well and this is how all the blocks are chained. Modifying one block would change its hash, will require modification in all the subsequent blocks as well. This makes Block chain technology very very trustworthy and secure.
Once a data is verified by the BlockChain, it cannot be altered again. New data must be verified by a majority of the network participants, meaning that the responsibility for blockchain security and trustworthiness is shared rather than taken over by a single, central entity. The BlockChain is completely OpenSource, which means it can be viewed by anyone.