Blockchain
What Is a Blockchain
A blockchain is a digital system that records transactions across many computers, making it very difficult to change or tamper with the data. It's the technology behind cryptocurrencies like Bitcoin and Ethereum, but it can also be used for other things, such as tracking products in a supply chain, creating automated contracts, and securing voting systems. A blockchain consists of a series of blocks, each containing a list of transactions and a cryptographic hash of the previous block. These blocks are linked together, and each block has a unique code that keeps the information safe and connected to the previous block.
In a blockchain, transactions are confirmed by a network of computers, called nodes, using methods like Proof of Work (PoW). Once a group of transactions is verified, a new block is added to the chain and shared with all participants, making the system secure and transparent. Since blockchain is decentralized, it’s maintained by a network of users, not controlled by a single authority, which adds to its security and trust.
While blockchain is best known for running cryptocurrencies, it has many other uses. For example, it can track products as they move from manufacturer to delivery, helping to ensure authenticity and reduce fraud. Blockchain can also automate contracts (smart contracts) without the need for a middleman, and make voting more secure by ensuring votes can't be tampered with. In healthcare, blockchain can securely store and share medical records.