Blockchain is a distributed ledger technology that underlies cryptocurrencies like Bitcoin, Ethereum, and others. A blockchain is essentially a decentralized and transparent database of transactions that is maintained by a network of computers.
Every time a transaction is made on a blockchain, it is validated and added to a block of transactions. Once the block is full, it is added to the blockchain and cannot be altered. This creates an immutable record of all transactions on the network.
The use of blockchain technology provides several benefits for cryptocurrencies, including decentralization, security, and transparency. Because the blockchain is decentralized, it is not controlled by any central authority, making it resistant to censorship and fraud. The use of cryptography ensures that the transactions are secure and tamper-proof, and the transparency of the blockchain allows anyone to verify the authenticity of transactions.