Find out exactly what a block in a blockchain is and the important role this piece plays within the most revolutionary technology since the creation of the Internet.
In blockchain technology, a block is a concept designed to optimize the process of validating the transactions that are carried out.
On the Bitcoin blockchain, each block is generated through the Proof of Work (PoW) system, when a computer (or a pool of them) solves the problem or puzzle automatically set by the network.
Bitcoin handles dozens of transactions per second. Validating each of these operations individually would be completely unfeasible and would be a long and tedious process.
So the creation of blocks was devised, through bitcoin mining, which make it possible to reference all the information in a block through a hash and make it more manageable and therefore more efficient.
The fundamental structure of a block is a header containing data from the previous block and some data from the transactions made by users. It also adds other data such as a timestamp and the nonce.
All the transactions are used to generate a central substructure, called a Merkle tree, which is a summary of all the transactions contained in the block, resulting in a Merkle Root, which is what is added to the block to reference all the transactions.
As a recurring analogy, blockchain is often likened to the concept of a Ledger (general ledger or accounting book).
Following this analogy, if a blockchain network is a ledger, each block would be one of the pages that make it up, where all the transactions carried out within the network are recorded.
These blocks usually have different additional conditions. The maximum size of each block is set, which may depend on the blockchain structure, and how often a new block is created is also established. Below, we give you Bitcoin and three of its most important forks as examples:
- Bitcoin (BTC): 1MB blocks every 10 minutes.
- Bitcoin Cash (BCH): 8MB blocks every 10 minutes
- Bitcoin Gold (BTG): 1MB blocks every 10 minutes
- Bitcoin Private (BTCP): 2MB blocks every 2.5 minutes
