From HomoExcelsior

n. A "crypto identity." A way for individuals to set up accounts with various organizations without revealing more information than they wish. Users may have several digital pseudonyms, some used only once, some used over the course of many years. Ideally, the pseudonyms can be linked only at the will of the holder. In the simplest form, a public key can serve as a digital pseudonym and need not be linked to a physical identity.

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