words per minute
3
SurajitBasak
00:00
Speed
You might heard about Bitcoin. In 2009 Satoshi Nakamoto brought the idea of Bitcoin. Currently one Bitcoin has 66,850.97 USD market value. Bitcoin is developed using the blockchain concept.
So, what is block chain?
The idea of blockchain is not new. Stuart Haber and W.Scott Stornetta in 1991 also envisioned something similar to blockchain. They create their first cryptographically secure chains of blocks with timestamps so that no one can tamper them. Block chain is a chain of blocks which holds information. Every blocks are chained using the hash function. One block has many properties like index, timestamp, data, hash, previous hash etc. The first is is a genesis block. And the second block is connected with the previous hash. Let's say you want to make a block which has those properties, when you are making a first block it has "0" hash. it means it does not have any previous block and it is called "Genesis Block". And when second block is created it will hold the hash of "Genesis block" with previous hash property. For this reason it is difficult to tamper its data if the size of blockchain increases. Even if you break the algorithm and successfully tampered any data of any blockchain it will not work. Because those block chains are decentralised. It means every blockchains are distributed in many computer connected with peer to peer networks. If you successfully break the block chain, you also need to break those blockchains in top 50% computers. Only then your tampered blockchain will be accepted.