+**Hardness** describes a material's resistance to localized plastic deformation, such as indentation, abrasion, or scratching. It is a fundamental [material property](/wiki/material_property) vital in engineering, indicating how well a substance resists wear and surface alteration, often quantified by scales like [Mohs](/wiki/mohs_scale).
+## See also
+- [Strength](/wiki/strength)
+- [Toughness](/wiki/toughness)
+- [Ductility](/wiki/ductility)
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