IOTA is a new open-source distributed ledger (register) that is not based on a blockchain. It's pioneering quantum-proof protocol, dubbed Tangle, produces unique new features such as zero fees, fast transactions, safe data processing, Quantum Proof, etc. The main feature of the system is it's operating on a unique DAG protocol. This is a directed acyclic mathematical graph that streamlines micro-payments work. The basic sense of the Tangle is that every transaction is approved by 2 previous ones. Simply speaking, all system transactions are confirmed by each other, and if problems are encountered, log systems interact with other transactions. If the distance between sections includes several blocks, one section implicitly approves the second. But the system does not confirm conflicting nodes, if they come across.