A chipped stone knife, a clay figurine, a rusted iron nail: these are artifacts, objects made or modified by humans. The category is broader than it first appears. A naturally shaped rock carried to a camp and used as a hammerstone counts. So does a modern plastic bottle if it ends up in a future excavation. Archaeologists care about artifacts because they are durable traces of behavior that would otherwise leave no record.

Not every artifact is glamorous. Most of what fills museum storage is debitage, the waste flakes struck off during toolmaking, or plain body sherds from broken pots. These humble items often reveal more than spectacular finds because they are common and their distribution patterns show where people lived, worked, and threw things away. An artifact's meaning comes from context: a gold mask in a tomb tells a different story than the same mask in a trash pit.

How archaeologists classify them

• Material: stone, bone, ceramic, metal, glass, organic.
• Function: tool, ornament, container, weapon, ritual object.
• Technology: how it was made and what that implies about skill.
• Provenance: where it was found and with what.

Looting destroys context, which is why the black market in antiquities is such a loss to knowledge.