A hashlock is a type of restraint that restricts the spending of an output until a specified piece of data is publicly revealed. Once a hashlock is opened publicly, other hashlock secured using the same key can also be opened. Hashlock helps in creating multiple outputs that are all restricted by the same hashlock and due to this each and every one of them becomes spendable at the same time. Hashlocks are used independently but they are mostly described as a part of a system known as Hashed Timelock Contracts.
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