The term blockchain refers to a technical concept that combines individual data records (e.g. transactions) into blocks and ensures data integrity with the aid of cryptographic procedures. The blocks are sequentially linked so that both the time sequence and the data integrity of the entire dataset is ensured. A manipulation of a data record would thus be detectable. With a blockchain, new data is combined into a new block and is then appended to the existing blockchain.
Researchers are convinced that blockchain will revolutionize our economic system because it will create a robust trust system for decentralized cooperation. Brokers become superfluous. Assets that were blocked can now be traded. New services offered in public blockchain networks allow for greater efficiencieny and added value.
A lot of research and work is still required to make blockchain useful on a wide variety of applications. The fields of application are manifold. A distributed ledger can show an account balance, the status of a contract (Smart Contracts) or ownership or origin relationships. All not in a single central database, but in many copies distributed all over the world.
Cryptologic algorithms are the central element of blockchain technology. To interact with a blockchain, a cryptographic key pair must be generated. This pair consists of a public key that serves as an address and a private key that allows full access to this address.