The blockchain is a storage system that aggregates incoming information into data blocks, validates them and chronologically chains them together. Once a data block has been added to the blockchain, it can no longer be modified.
Each new data block is duplicated and distributed to all participants of the blockchain network. The blockchain can therefore also be described as a decentralised database in which every transaction is registered and documented by all participating parties. Every modification can always be tracked and creates additional transparency.
The fundamental advantage is that unintentional manipulation is almost impossible as the data is not stored in a single instance, unlike in conventional databases.