**3. Blockchain technology**

This chapter provides a brief explanation of blockchain technology. Only aspects relevant to this article are described, and they are described with relevance to supply chains in mind.

Blockchain technology is a layer on the internet. It consists of "blocks" that are chained together. A block contains sets of data, similar to records in a database. While a block contains several sets of data, this chapter simplifies the technology into assuming each block contains one set of data in order to explain the principle.

A set of data contains


A new database record will be created each time a transaction happens. In supply chains, an example of a transaction is loading of the container onto a ship.
