Hierarchy (disambiguation)

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A hierarchy is an arrangement of units into related levels of different weights or ranks, meaning that levels are considered "higher" or "lower" than one another. The term, which originally meant rule by priests, is now generalised and describes systems with a linear concept of subordinates and superiors and where each level has only 1 direct parent level. Hierarchies are typically depicted as a tree structures.

Hierarchy may also refer to:

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In software engineering and computer science, abstraction is:

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Order, ORDER or Orders may refer to:

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