What is
a Blockchain?

Blockchain is the name of the technology that Bitcoin, many other cryptocurrencies and NFTs use. A blockchain consists of blocks of data linked together in a chain. These concatenated data blocks are located on globally distributed and networked data servers. The identical blockchain is located on each server and is updated simultaneously on all servers.

The system is, therefore, decentralised because there is no central server – all servers have the same hierarchy. This makes the system fail-safe – if one server fails, the identical blockchain is available on all other servers. The blockchain can also be thought of as a train made up of multiple carriages, each carrying multiple passengers.

Blockchain blocks also transport something; only here, the passengers are digital data. They are all linked chronologically. This is important because the information they contain is interdependent.


A block records all transactions in a defined period of a cryptocurrency.

Each block contains a series of digital transactions that occurred within a specific time. The first block of a blockchain contains the foremost transactions, while subsequent blocks have transactions that happen later. All blocks represent the entirety of the transactions that ever took place up to the creation of the last block.

A block records all transactions in a defined period. A new block is generated and appended to the previous block when the period has lapsed. For NFTs and cryptocurrencies, the blockchain is a kind of digital balance sheet from which the following data emerge:





in what quantity

This information can be viewed for every single transaction – the blockchain is, therefore, highly transparent. So that the blockchain always runs synchronously on all servers, they follow a cryptocurrency-specific control – the consensus algorithm. This network of decentral servers has no central server that can be attacked. A blockchain is, therefore, very secure.