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An explanation of Blockchain

by AprilSix Proof


Blockchain is one of the hottest technologies around right now. However, there is as much confusion as there is hype around what Blockchain actually is and what it can do. Here is a short explanation on what blockchain is and how it could revolutionise the world.

What is it?

Blockchain and its associated cryptocurrency, Bitcoin, were invented in 2009 as an alternative system that sought to eliminate the middleman from online financial transactions. The middleman in financial transactions usually validates the transactions and guarantees that one party can ‘trust’ another. In the physical world, if I give you £20, you know that I gave you that money; you can trust the transaction took place. You physically have the money and I do not. But, digital money is not like physical money; the middleman has to exist to stop me from copying money or sending money I don’t have for example. There needs to be a record of what is transferred and who to – banks play this role of a central ledger of all transactions.

Blockchain offers an alternative to trusting a central third party, as it is a secure publicly owned ledger that records every Bitcoin transaction that occurs within the system, providing distributed ‘digital trust’. It eliminates the need for everyone to trust a single intermediary, which can be problematic as they can falsify or manipulate records at will (forgery), cause unnecessary delays (closed at the weekend) or implement a transaction fee (50p charge).

So how does it work?

Very simply, let’s take 5 computers and call it a blockchain system. If computer 1 sends a Bitcoin to computer 2, that transaction would be sent to computers 3, 4 and 5 to verify. Once at least 51% of the computers on the system agree that the transaction took place and all the details are correct, the transactions would be added to the public ledger – the blockchain – that is shared between all of them. Each time a transaction is processed, a new data ‘block’ is added to the chain, which contains a record of that transaction. Each block’s code links back to another’s, making in nearly impossible to alter the code of one without altering the whole chain, giving a huge advantage by being inherently secure by design.

The computers that process the algorithms to create the blocks are known as ‘miners’. Their incentive and reward for this is bitcoin, which is given randomly to one of the computers. In summary, it is an autonomous, decentralised, secure system for financial transactions.

Other blockchains

A number of new blockchains have emerged recently, all of which take the principle of a decentralised database and add to it. One of the most promising is Ethereum, which allows for a technology called ‘smart contracts’. Rather than just acting as a record, Ethereum allows executable actions to be coded in to occur later in time. Imagine last year you bet me £100 that Arsenal finish in the top 4 at the start of the season. If we did this on Ethereum, that money would automatically be given to me at the end of the season with no compromise. This has all sorts of business applications. Ethereum also allows anyone to build apps on top of it while using the security of its platform.

Golem, another blockchain, takes the idea on a different tangent to create a huge supercomputer. Say you have a huge task that takes huge amounts of processing power and time to solve, such as particle modelling or even 3D rendering, Golem aims to solve this problem by cutting that calculation into smaller parts and distributing them to idle computers on the blockchain to solve. Each computer would be quickly able to solve the smaller parts, after which the pieces are put back together to reform the completely processed task.

The applications of blockchain of technology are enormous. Although this is a very simplistic explanation, hopefully this blog goes some way to explain what the technology actually is.

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