ZK-STARKs time: The ZK STARK whitepaper came out in 2018 (alongside a main component, called FRI). At that time, we already saw that Elliptic curve based ZK SNARKs can solve privacy for blockchains, and it seemed to be all that the world hoped for. So, why a completely new construction? what was top of mind for us? The main advantages of ZK STARKs were the following: • Transparency (the T of STARK) -- This means no "toxic waste" setup, as needed in the ceremony in the case of SNARKs. This is very important for trust. To explain -- There is no trusted set up, so transparent ZK-STARKs can be trusted even if used by Darth Vader. • Post quantum safety -- Back in 2018, not that many spoke about the quantum threat and how it may destroy elliptic curve cryptography. But ZK STARKs are post quantum secure and in fact require only the existence of a secure hash function. This turned out to be important in our day and age of super intelligence and its threat to standard hardness assumptions like those underpinning RSA, DH, ECDSA, Lattice based constructions etc. • Field-agnostic -- The ZK-SNARKs of Zcash required very specific algebraic strucutres (finite fields) and large ones at that. STARKs, on the other hand, work over literally all finite fields, including binary ones and small prime fields, which is better for efficient computation time. To the non-mathematicians, this means much greater speed and scale. For instance, we clocked M31 field arithmetic (used by our latest and greatest STARK prover, S-two) to be 100x faster than the arithmetic we used for our first generation prover which required a 256-bit field(!). • Scalability -- The fact that they work over any field, plus the lack of need for a trusted setup, means that we didn't need to change anything in the onchain verifier even as we scaled and scaled again the size of computations we handled. Summarizing -- transparency, post-quantum security, efficiency and scale were the huge benefits that ZK STARKs offered the world in 2018. By now, they've become the gold standard for safe ZK scale and privacy. THE END