The blockchain is usually associated with Bitcoin and other cryptocurrencies, but these are just the tip of the iceberg. And it is that this technology, which has its origins in 1991, when Stuart Haber and W. Scott Stornetta described the first work on a chain of cryptographically insured blocks, was not noticeable until 2008, when it became popular with the arrival of bitcoin. But currently its use is being demanded in other commercial applications and an annual growth of 51% is projected by 2022 in several markets, such as that of financial institutions or Internet of Things (IoT), according to MarketWatch.
What is blockchain?
The blockchain, better known by the English term blockchain, is a unique register, agreed and distributed in several nodes of a network. In the case of cryptocurrencies, we can think of it as the accounting book where each of the transactions is recorded.
Its operation can be complex to understand if we delve into the internal details of its implementation, but the basic idea is simple to follow.
In each block it is stored:
a number of valid records or transactions,
information regarding that block,
its link with the previous block and the next block through the hash of each block - a unique code that would be like the fingerprint of the block.
Therefore, each block has a specific and immovable place within the chain, since each block contains hash information from the previous block. The entire chain is stored in each node of the network that makes up the blockchain, so an exact copy of the chain is stored in all network participants.
As new records are created, they are first verified and validated by the network nodes and then added to a new block that links to the chain.
Finally, since each block is mathematically linked to the next block, once a new one is added to the chain, it becomes unchanged. If a block is modified its relationship with the chain is broken. That is, all the information recorded in the blocks is immutable and perpetual.
In this way blockchain technology allows us to store information that can never be lost, modified or deleted.
In addition, each node of the network uses certificates and digital signatures to verify the information and validate the transactions and data stored in the blockchain, which ensures the authenticity of said information.