A Node in the context of cryptography refers to a computing entity in a blockchain network or other distributed cryptographic system. Professionally, a Node is a point in the network that runs specialized software that allows it to participate in transaction validation, data storage, and maintaining network security and consistency. Each Node has a complete or partial copy of a distributed ledger of transactions, known as a blockchain, and communicates with other Nodes to reach consensus on the correct state of this ledger.

In this context, Nodes function as an integral part of the infrastructure that supports the operation of cryptographic networks. This includes verifying transactions, storing copies of the blockchain, and transmitting transaction information between other Nodes. The involvement of Nodes in the process of validating and synchronizing transactions makes them critical to the overall security and integrity of the cryptographic system.