Substrate is a framework for making custom blockchains, made available by Berlin based Parity Technologies, who are until now the best known for making the second-most popular (after the official one, Go Ethereum) client for the Ethereum blockchain, also called Parity. Parity Technologies is led by Gavin Wood, one of the inventors of Ethereum and as such one of the true authorities in the blockchain space. Based on their significant experience in developing the Ethereum blockchain, Parity devised Substrate as a framework/toolkit for those who wish to design their own blockchains as opposed to having to build on top of e.