hierchical deterministic keys

Definition

A HDK type is a type of deterministic bitcoin wallet derived from a known seed, that allow for the creation of child keys from the parent key. Because the child key is generated from a known seed there is a relationship between the child and parent keys that is invisible to anyone without that seed. The HD protocol (BIP 32) can generate a near infinite number of child keys from a deterministically-generated seed (chain code) from its parent, providing the functionality of being able to recreate those exact same child keys as long as you have the seed.
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