A blockchain records transactions in a distributed ledger that participants can verify without a single owner controlling the data, offering a shared history that is harder to alter than a traditional database.

Transactions are submitted to the network, checked against predefined rules, grouped into blocks and linked by cryptographic hashes, making any change to earlier records detectable.

Security and consensus are provided by mechanisms such as proof‑of‑work or proof‑of‑stake, each with different resource needs and trust assumptions.

Blockchains can be public, allowing anyone to join under the protocol, or permissioned, restricting read, write or validation rights to approved participants; the choice of permissions often matters more than the technology label itself.

Typical use cases include supply‑chain tracking, digital asset registries and settlement processes where multiple parties need an agreed‑upon history and do not want a single entity to control updates.

However, a blockchain cannot verify that physical inspections or sensor readings are accurate; the point where real‑world data enters the ledger remains a trust challenge.

Before adopting blockchain, organisations should define participants, data types, governance structures and dispute‑resolution processes, and compare the costs and benefits against a conventional database with signed receipts.

For businesses, piloting a narrow use case—such as recording hand‑over events in a distribution network—helps assess transaction costs, privacy needs and the effort required to correct mistakes before scaling.

Consumers evaluating blockchain‑enabled services should verify what can actually be audited, review platform rules and account controls, and understand that transparency of outcomes does not eliminate financial risk.