Grin is a privacy-preserving digital currency built openly by developers distributed all over the world. Grin has no amounts and no addresses. Transactions can be trivially aggregated. To hide the origin of a newly created transaction, it gets relayed among a sub-set of peers before it is widely broadcasted. Grin is not controlled by any company, foundation or individual. The coin distribution is designed to be as fair as possible, with an emission of 1 GRIN per second. Mimblewimble leverages cryptography to allow past transaction data to be removed with no compromise on security. This avoids Grin collapsing under the weight of data having to be kept on chain.