Petroglyphs are images created by removing part of a rock surfaces by incising, pecking, carving, and abrading. Outside North America, scholars often use terms such as "carving", "engraving", or other descriptions of technique to refer to such images. Petroglyphs are found world-wide, and are often (but not always) associated with prehistoric peoples. The word comes from the Greek words petros meaning "stone" and glyphein meaning "to carve" (it was originally coined in French as pétroglyphe).
The term petroglyph should not be confused with pictograph, which is an image drawn or painted on a rock face. Both types of image belong to the wider and more general category of rock art. Petroforms, or patterns and shapes made by many large rocks and boulders in rows over the ground, are also quite different.
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