Blockchain is a distributed ledger technology that allows data to be stored across a network of computers in a secure, transparent, and immutable way. Unlike traditional databases that are centrally managed, blockchain operates on a decentralized model where each participant in the network has a copy of the entire ledger. Transactions are grouped into blocks and added to the chain in a linear, chronological order. Each block contains a cryptographic hash of the previous block, ensuring that once data is added, it cannot be altered without altering subsequent blocks, which requires consensus from the network.

Blockchain technology is best known as the underlying technology for cryptocurrencies like Bitcoin, but its applications extend far beyond digital currencies. It can be used in supply chain management, digital identity verification, smart contracts, and more, offering advantages such as increased transparency, security, and efficiency. By removing the need for intermediaries and enabling peer-to-peer transactions, blockchain has the potential to revolutionize industries and create new business models.