What is blockchain
Blockchain is a digital ledger technology that functions as a public, distributed, and immutable ledger. Instead of being stored on a single server or under the control of a single entity, blockchain is maintained by a network of independent computers known as nodes. Each of these nodes keeps a complete copy of the transaction history, ensuring transparency and security.
Information is grouped into blocks. Each block contains a set of transactions and a unique code called a "hash." When a new block is created, it includes the hash of the previous block, forming a continuous chain — hence the name blockchain. This cryptographic link between the blocks prevents old data from being altered without breaking the entire chain, making the system highly resistant to fraud.
Another essential point is consensus. For a new block to be added, the majority of the network must agree that the transactions are valid. This can be done through different mechanisms, such as proof of work (PoW) or proof of stake (PoS). This model eliminates the need for a central intermediary, allowing for direct and reliable transactions between people or systems.
In summary, blockchain is a secure, decentralized, and transparent way to record information, being used not only in cryptocurrencies but also in smart contracts, logistical tracking, digital identity, and many other sectors.
