“The blockchain is an incorruptible digital ledger of economic transactions that can be programmed to record not just financial transactions but virtually everything of value.”
- Don & Alex Tapscott, authors Blockchain Revolution (2016)
The blockchain is an undeniably ingenious invention – the brainchild of a person or group of people known by the pseudonym, Satoshi Nakamoto. But since then, it has evolved into something greater, and the main question every single person is asking is: What is Blockchain?
By allowing digital information to be distributed but not copied, blockchain technology created the backbone of a new type of internet. Originally devised for the digital currency, Bitcoin, (Buy Bitcoin) the tech community is now finding other potential uses for the technology.
Bitcoin has been called “digital gold,” and for a good reason. To date, the total value of the currency is close to $112 billion US. And blockchains can make other types of digital value. Like the internet (or your car), you don’t need to know how the blockchain works to use it. However, having a basic knowledge of this new technology shows why it’s considered revolutionary. So, we hope you enjoy this, What Is Blockchain Guide. And if you already know what blockchain is and want to become a blockchain developer (2018 – currently in high demand!) please check out our in-depth blockchain tutorial and create your very first blockchain
Picture a spreadsheet that is duplicated thousands of times across a network of computers. Then imagine that this network is designed to regularly update this spreadsheet and you have a basic understanding of the blockchain.
Information held on a blockchain exists as a shared — and continually reconciled — database. This is a way of using the network that has obvious benefits. The blockchain database isn’t stored in any single location, meaning the records it keeps are truly public and easily verifiable. No centralized version of this information exists for a hacker to corrupt. Hosted by millions of computers simultaneously, its data is accessible to anyone on the internet.
To go in deeper with the Google spreadsheet analogy, I would like you to read this piece from a blockchain specialist.
“Blockchain solves the problem of manipulation. When I speak about it in the West, people say they trust Google, Facebook, or their banks. But the rest of the world doesn’t trust organizations and corporations that much — I mean Africa, India, the Eastern Europe, or Russia. It’s not about the places where people are really rich. Blockchain’s opportunities are the highest in the countries that haven’t reached that level yet.”
- Vitalik Buterin, inventor of Ethereum
Computer connected to the blockchain network using a client that performs the task of validating and relaying transactions) gets a copy of the blockchain, which gets downloaded automatically upon joining the blockchain network.
Together they create a powerful second-level network, a wholly different vision for how the internet can function.
Every node is an “administrator” of the blockchain, and joins the network voluntarily (in this sense, the network is decentralized). However, each one has an incentive for participating in the network: the chance of winning Bitcoins.
Nodes are said to be “mining” Bitcoin, but the term is something of a misnomer. In fact, each one is competing to win Bitcoins by solving computational puzzles. Bitcoin was the raison d’etre of the blockchain as it was originally conceived. It’s now recognized to be only the first of many potential applications of the technology.
There are an estimated 1600 Bitcoin-like cryptocurrencies (exchangeable value tokens) already available. As well, a range of other potential adaptations of the original blockchain concept are currently active, or in development.
By design, the blockchain is a decentralized technology.
Anything that happens on it is a function of the network as a whole. Some important implications stem from this. By creating a new way to verify transactions aspects of traditional commerce could become unnecessary. Stock market trades become almost simultaneous on the blockchain, for instance — or it could make types of record keeping, like a land registry, fully public. And decentralization is already a reality.
A global network of computers uses blockchain technology to jointly manage the database that records Bitcoin transactions. That is, Bitcoin is managed by its network, and not any one central authority. Decentralization means the network operates on a user-to-user (or peer-to-peer) basis. The forms of mass collaboration this makes possible are just beginning to be investigated.
As web infrastructure, you don’t need to know about the blockchain for it to be useful in your life.
Currently, finance offers the strongest use cases for the technology. International remittances, for instance. The World Bank estimates that over $430 billion US in money transfers were sent in 2015. And at the moment there is a high demand for blockchain developers.
=The blockchain potentially cuts out the middleman for these types of transactions. Personal computing became accessible to the general public with the invention of the Graphical User Interface (GUI), which took the form of a “desktop”. Similarly, the most common GUI devised for the blockchain are the so-called “wallet” applications, which people use to buy things with Bitcoin, and store it along with other cryptocurrencies.
Transactions online are closely connected to the processes of identity verification. It is easy to imagine that wallet apps will transform in the coming years to include other types of identity management.
By storing data across its network, the blockchain eliminates the risks that come with data being held centrally.
=Its network lacks centralized points of vulnerability that computer hackers can exploit. Today’s internet has security problems that are familiar to everyone. We all rely on the “username/password” system to protect our identity and assets online. Blockchain security methods use encryption technology.
The basis for this are the so-called public and private “keys”. A “public key” (a long, randomly-generated string of numbers) is a users’ address on the blockchain. Bitcoins sent across the network gets recorded as belonging to that address. The “private key” is like a password that gives its owner access to their Bitcoin or other digital assets. Store your data on the blockchain and it is incorruptible. This is true, although protecting your digital assets will also require safeguarding of your private key by printing it out, creating what’s referred to as a paper wallet.
Ethereum is an open-source, public, blockchain-based distributed computing platform featuring smart contract functionality. It provides a decentralized Turing-complete virtual machine, the Ethereum Virtual Machine (EVM), which can execute scripts using an international network of public nodes. Ethereum also provides a cryptocurrency token called "ether", which can be transferred between accounts and used to compensate participant nodes for computations performed."Gas", an internal transaction pricing mechanism, is used to mitigate spam and allocate resources on the network.
Proof of work is a mining process in which a user installs a powerful computer or mining rig to solve complex mathematical puzzles (known as proof of work problems). Once several calculations are successfully performed for various transactions, the verified transactions are bundled together and stored on a new ‘block’ on a distributed ledger or public blockchain. Mining verifies the legitimacy of a transaction and creates new currency units.
The work must be moderately difficult for the miner to perform, but easy for the network to check. Multiple miners on the network attempt to be the first to find a solution for the mathematical problem concerning the candidate block. The first miner to solve the problem announces their solution simultaneously to the entire network, in turn receiving the newly created cryptocurrency unit provided by the protocol as a reward.
As more computing power is added to the network and more coins are mined, the average number of calculations required to create a new block increases, thereby increasing the difficulty level for the miner to win a reward. In proof of work currencies, miners need to recover hardware and electricity costs. This creates downward pressure on the price of the cryptocurrency from newly generated coins, thus encouraging miners to keep improving the efficiency of their mining rigs and find cheaper sources of electricity.
Bitcoin is an example of a cryptocurrency that uses the proof of work system.
Unlike the proof of work system, in which the user validates transactions and creates new blocks by performing a certain amount of computational work, a proof of stake system requires the user to show ownership of a certain number of cryptocurrency units.
The creator of a new block is chosen in a pseudo-random way, depending on the user’s wealth, also defined as ‘stake’. In the proof of stake system, blocks are said to be ‘forged’ or ‘minted’, not mined. Users who validate transactions and create new blocks in this system are referred to as forgers.
In most proof of stake cases, digital currency units are created at the launch of the currency and their number is fixed. Therefore, rather than using cryptocurrency units as reward, the forgers receive transaction fees as rewards. In a few cases, new currency units can be created by inflating the coin supply, and forgers can be rewarded with new currency units created as rewards, rather than transaction fees.
In order to validate transactions and create blocks, a forger must first put their own coins at ‘stake’. Think of this as their holdings being held in an escrow account: if they validate a fraudulent transaction, they lose their holdings, as well as their rights to participate as a forger in the future. Once the forger puts their stake up, they can partake in the forging process, and because they have staked their own money, they are in theory now incentivized to validate the right transactions.
This system does not provide a way to handle the initial distribution of coins at the founding phase of the cryptocurrency, so cryptocurrencies which use this system either begin with an ICO and sell their pre-mined coins, or begin with the proof of work system, and switch over to the proof of stake system later.
Cyptocurrencies that currently run the proof of stake system are BlackCoin, Lisk, Nxt and Peercoin, among others.