What is the Blockchain ?
The blockchain technology is a technology center around the storage and the distribution of information in a more secure, more efficient way. It can be pictured as a decentralized ledger where every bit of information is distributed not copied. Where the blockchain is considered as the « new internet » is because every transaction between users is save and shared between those users without the need of a third party. This allows every single user to verify the validity of the blockchain.
If you want to have a more detailed picture of the Blockchain, I supposed that you already came across collaborative document or spreadsheet like google sheets of Microsoft office online. The blockchain works in the same way. Picture an online spreadsheet open by several users at the same time. As soon as a cell is updating all the user have the information and the cell is no longer available. That is a straightforward way to explain the blockchain. The simple fact that all users have access to the information in a decentralized way is much more complicated (just not to say impossible) for hackers to alter the database. This is a quote that can be used to explain the blockchain:
Imagine the number of legal documents that should be used that way. Instead of passing them to each other, losing track of versions, and not being in sync with the other version, why can’t all business documents become shared instead of transferred back and forth? So many types of legal contracts would be ideal for that kind of workflow. You don’t need a blockchain to share documents, but the shared documents analogy is a powerful one.” — William Mougayar, Venture advisor, 4x entrepreneur, marketer, strategist, and blockchain specialist
The Blockchain have multiple use cases. The most know use case is the cryptocurrency, but the blockchain can have application like tracking fraud, sharing patent for intellectual property or music rights for example.
Now that you have a little understanding of the Blockchain, let us see how it works with the main concepts the blocks, the nodes, and the miners.
The Blocks
As the name suggest, the blockchain is a succession of block forming a chain. Every block is composed of 3 elements. The data inside the block, a nonce (a 32-bit whole number) and the hash a 256-bit number link to the nonce.
The Miners
The miners are here to create new blocks. They create those blocks using a process call the mining that consist of using a special software to find a nonce with an acceptable hash. It is an overly complex operation because of the 4 billion combination to be mined.
The Nodes
The nodes are every single electronic device that can connect to the chain.
Now that you have every piece of the puzzle let us try to rewrite a definition with all of that.
The blockchain is decentralized ledger were the miners use a process called mining to create new blocks that will be wed to the chain. That blockchain will be copied to the nodes to assure the transparency of the blockchain.