This article aims to be the first of many about the Blockchain technology.
There are lots of romantic blockchain definitions; for some people it is just a worldwide ledger, for others it is the Internet timestamp.
We will describe it as we know it: a distributed database in a decentralized peer network.
This distributed database is partially or totally located in every node of the network, the latter automatically inserting new valid entries, without the intervention of a guaranteeing third party.
The blockchain technology was born in 2009 with Bitcoin, a cryptocurrency that takes pride in its 19 billion-dollar market cap and whose blockchain is the blockchain par excellence.
Bitcoin is not the only cryptocurrency: since 2009 the number of new blockchain projects has experienced a significant increase.
This growth shows a general discomfort caused by mounting lack of transparency in the use of personal data and a failure of modern hierarchical systems.
Algorithmically.
Every cryptocurrency, or token, such as Bitcoin and Ethereum, employs distributed consensus algorithms, which manage the insertion of new entries in the blockchain, each according to its own peculiarity.
Every time a node of the network inserts in the chain a valid block (that is verified by the network), it is rewarded with one or more tokens of the relative blockchain.
This mechanism motivates the nodes in the network to work properly, so that the nodes do not damage the network.
This process is called Mining.
The most popular algorithm is the Proof Of Work employed in Bitcoin and other crypto like Ethereum or Monero.
POW is an algorithm demanding a lot of computational resources, subsequently a massive use of electricity.
Along the way several "green" algorithms have been employed like the Proof Of Stake (POS), to which Ethereum will probably recur, or variants of it like the Delegated Proof Of Stake (DPOS) implemented by Lisk.
Like most technologies, the blockchain technology has a strong impact on the social-economic world as well.
In the next articles we will write more about this impact and how cryptocurrencies are trying to change the world.