Blockchain is a decentralized, distributed, and immutable digital ledger used to record transactions across many computers.

In the context of transportation and logistics, its main purpose is to create a single, shared source of truth that all parties in a supply chain can trust.

Its key benefits are: - **Transparency & Traceability:** Every step in a shipment's journey (e.

g.

, leaving the warehouse, clearing customs, arriving at the port) can be recorded as a block on the chain.

All authorized participants can see this history, providing end-to-end visibility and making it easy to trace the origin of delays or issues.

- **Security:** Because the ledger is distributed and cryptographically linked, it is extremely difficult to alter or tamper with records.

This enhances the security of sensitive documents like bills of lading or customs declarations.

- **Efficiency & Automation:** Smart contracts, which are self-executing contracts with the terms of the agreement written into code, can be built on the blockchain.

For example, a smart contract could automatically release payment to a carrier as soon as an IoT sensor confirms that a shipment has been delivered to the correct location and in the right condition.

While adoption is still growing, blockchain offers a powerful way to reduce fraud, eliminate paperwork, and build trust among the many actors in a complex logistics network.