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Decentralised identity models lets users share identity verifications over a decentralised network. The identity itself is not stored on the blockchain network, instead it uses verification method that lets you verify a claim without actually sharing the identity. Your identity is with your control at all times and is never actually shared, eliminating most identity theft problems. Different networks can reserve did identifiers like domain names and can then be used to issue identities, so a DID issued by google could look like Google or US government.