what is mean blockchain?

In simple terms “how the internet is for an email, the Blockchain is for Bitcoin (CryptoCurrencies). So now if i ask you what is internet, then you cannot give a single line answer about what internet is!. In the same way it is hard to define Blockchain in single line.

Originally Blockchain was invented for Bitcoin transactions but now it is not just confined to Bitcoins but there are innumerable use cases of Blockchain as a Technology. There are Public Blockchains, Private Blockchains, Permissioned and Permissionless blockchains. So the Scope and implementation of the Blockchain technology is wider.

We can describe Blockchain with following points.

• Blockchain is a De-Centralised Peer to Peer Network
• Blockchain is Distributed Ledger
• Blockchain is Secure
• Blockchain is immutable

Blockchain is basically a chain of blocks created by validating transactions and adding to the chain. The validated transactions constitute blocks in a blockchain and each block links to previous block using hash pointer. There is something called proof of work in blockchain, which basically is a mechanism used to validate and approve the transactions to be added as a block to the chain. There are various consensus algorithms used to create proof of work in different blockchain based projects.

The blockchain technology is revolutionary and hence finds its applications in various sectors such as finance, insurance, health care, transportation, housing and much more.

Ethereum smart contracts are the most popular use cases of ethereum blockchain and in high demand.

The hyperledger project is other most popular blockchain based open source projects catering to multiple use cases.

IOTA is other blockchain technology based project targeted for machine to machine transactions and IOT applications but it has neither a block nor chain!