IOTA is an open-source distributed ledger protocol that has an interesting feature set compared to blockchain. Its central technology is called the ‘Tangle’ which is quite distinct. The IOTA Tangle is a quantum-proof Directed Acyclic Graph. Transactions are free and an unlimited number can be confirmed by the network every second. Throughput grows as activity grows, which means that it actually runs quicker when more is asked of it. In contrast to blockchain infrastructure, IOTA does not draw a distinction between those who use the system from those who validate the transactions; in contrast, it validates them as a normal consequence of utilizing the ledger, so it effectively avoids centralization. IOTA’s priority at the moment is to facilitate the Internet-of-Things (IoT). You can read more about IOTA’s technical underpinnings here— https://iota.org/IOTA_Whitepaper.pdf.