Proof of Work
Bitcoin uses a proof-of-work system. What is proof of work? It is a piece of data that's very hard to produce (meaning it takes a lot of time or costs a lot of money) but can be easily verified by others, and it satisfies specific requirements. With bitcoin, proof of work is a competition among miners who want to add a block to the Blockchain—meaning they have to find the nonce value for the block by solving a mathematical puzzle. Once a miner discovers a nonce value, he or she spreads the word throughout the network, and if other miners validate the claim, the miner is rewarded with 12.5 bitcoins or another form of compensation. Finding a nonce value also adds that block to the Blockchain.
Choosing a nonce value is the primary objective of miners. They have to find a value that is less than the target value. If they find a value greater than the target, then their mining effort is rejected. But if they can successfully generate a hash value using the nonce that is less than the target value, then their effort is accepted. This is where the entire computational power of the miner is used—to generate the hash value.
Finding a nonce value requires a lot of time, money, and resources. When the nonce value is found, the miner spreads the word about finding this value, other miners attempt to validate the claim, and if it's verified, the miner gets the reward. So a miner is rewarded for being the first one to find the nonce, and that adds a block to the Blockchain.
As mentioned, as of today, the reward is 12.5 bitcoins. Every four years, the amount of bitcoin a miner can earn is reduced by half. Mining is the only way new bitcoins can be generated, and it ensures that there's a limit to how many bitcoins can exist in the market.
Miners
Mining is the process of a miner being rewarded for finding the appropriate nonce first. Miners get paid in Bitcoins, and a successful verification is the only way the Bitcoins get added to the network. That is the concept of mining, and when a miner has completed the proof of work consensus, he is rewarded.
A miner's fee is 12.5 Bitcoins for adding a block onto the Blockchain; however, the reward reduces by half every four years. When the fourth year approaches, the Bitcoin reward will go down to 6.25 Bitcoins, and miners also get the sum of all the transaction fees for a particular block.
Blockchain Career Guide
A Guide to Becoming a Blockchain DeveloperDOWNLOAD NOWBlockchain Career Guide
The Walmart Problem
Walmart was facing an issue where people were returning goods citing quality issues. Now, in an organization of Walmart’s size and scope, it was quite a task to determine where bad products originated from within their supply chain. Their supply chain involved the following steps:
/walmart
To ensure their reputation wasn’t tarnished, they incorporated blockchain into their supply chain. Each event and detail within each step of the supply chain was logged. Now, in the scenario where a product was deemed bad and returned, Walmart would be able to determine where the issue with the product originated from in the supply chain.
Other Fields That Use Blockchain
The financial services industry is an open field that uses blockchain technology extensively, but it's not the only one. Forbes mentions healthcare, crowdfunding, and ride-sharing in its article "Eight Ways Blockchain Will Impact the World Beyond Cryptocurrency." Let's look at a few other fields.
Travel
Blockchain technology can be used for things like:
Tracking luggage, especially with multiple flights in one itinerary and international flights
Identifying passengers, saving time, and reducing lines and wait times
Making and accepting payments for services
Music
The rise of digital music has posed problems regarding issues like piracy and artist compensation. Blockchain can:
Help prevent piracy (illegal sharing) of music files
Be used to compensate artists for purchased songs and albums
Cyber Security
Even a giant company like Lockheed Martin is using Blockchain in its cybersecurity efforts. Blockchain can:
Help secure sensitive data, thanks to its cryptography feature
Eliminate the need for passwords, because users and devices can be authenticated using the public and private keys
Human Resources
Blockchain technology is a natural fit for improving time-consuming and costly HR procedures. For example, it can:
Eliminate the need to run individual verification checks on potential employees—blockchain transactions can store data regarding identity and employment history
Track payments and expenses, making things like paying taxes much easier for both employers and employees
Blockchain as a Use Case in Banking
Blockchain finds excellent use in banking. As of now, a user validates his identity to each bank he goes to, over and over. Is there a way we can ease the process with Blockchain? The answer is yes. We can use truffle, ethereum, ganache, and smart contracts, which are part of the Blockchain technology ecosystem, to make it work.