Hashcash

Rarity: Common

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At a glance

Class

Invention

Domain

Science and technology

Knowledge cost

2

In collections

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What Wikipedia says

Hashcash is a proof-of-work system used to limit email spam and denial-of-service attacks. Hashcash was proposed in 1997 by Adam Back and described more formally in Back's 2002 paper "Hashcash – A Denial of Service Counter-Measure".

Excerpt from the Wikipedia article “Hashcash”, under the CC BY-SA 4.0 license. Read the article on Wikipedia