Blockchain, as the name suggests, is a chain of blocks created in such a way that data is saved in segments in order and only when one part is full, another is created and attached. In addition, each block has information about other parts of the chain. Such a complicated structure of the tool means that any unauthorized interference in the register is immediately captured and the blockchain immediately breaks. This scheme, combined with very advanced cryptographic tools, makes this solution one of the best for fintech and non-financial applications.