What exactly BLOCKCHAIN technology is?

By Qrious Tech Team LLP

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Blockchain is a way to make transactions and transfers online without the use of an intermediary. Instead of trusting a third party to keep the transaction history safe and accurate, blockchain lets you seal “pages” of transactions with a key code for security.

History of Blockchain

The very primitive form of the blockchain was the hash tree. This data structure was patented by Ralph Merkle in 1979, and functioned by verifying and handling data between computer systems that’s why it is also called Merkle tree. In a peer-to-peer network of computers, validating data was important to make sure nothing was altered or changed during transfer. It also helped to ensure that false data was not sent. In essence, it is used to maintain and prove the integrity of data being shared.

In 1991, the Merkle tree was used to create a “secured chain of blocks” — a series of data records, each connected to the one before it. The newest record in this chain would contain the history of the entire chain. And thus, the blockchain was created.

In 2008, Satoshi Nakamato conceptualized the distributed blockchain. It would contain a secure history of data exchanges, utilize a peer-to-peer network to time stamp and verify each exchange, and could be managed autonomously without a central authority. This became the backbone of Bitcoin. And thus, the blockchain we know today was born, as well as the world of cryptocurrencies.

How Does Blockchain Work?

1. Blockchain keeps a record of all data exchanges — this record is referred to as a “ledger” in the cryptocurrency world, and each data exchange is a “transaction“. Every verified transaction is added to the ledger as a “block”

2. It utilizes a distributed system to verify each transaction — a peer-to-peer network of nodes

3. Once signed and verified, the new transaction is added to the blockchain and cannot be altered

To begin, we need to explore the concept of “keys”. With a set of cryptographic keys, you get a unique identity. Your keys are the Private Key and Public Key, and together they are combined to give you a digital signature. Your public key is how others are able to identify you. Your private key gives you the power to digitally sign and authorize different actions on behalf of this digital identity when used with your public key.

In the cryptocurrency world, this represents your wallet address (public key) and your private key is what let’s you authorize transfers, withdrawals, and other actions with your digital property like cryptocurrencies. As an aside, this is why it’s so important to keep your private key safe — anyone who has your private key can use it to access any of your digital assets associated with your public key and do what they want with it!

There is also a concept called the “51% attack” — if for some reason 51% of a peer-to-peer network validates an otherwise invalid transaction, it will still get approved and added to the ledger by nature of how the validation process works. Maybe right now it’s unlikely to happen, but it is a security flaw that might have potential for exploitation in the future.

However, there are a lot of developers, users, and enthusiasts who truly believe blockchain technology is the future.