The depiction of gnomes has changed quite often over the years and remained different in different cultures. Originally many of them were conceived of as ugly, ground dwelling creatures that were less humanoid than the gnomes of today. In fact, they were more akin to small goblins and disfigured faeries, and acted more like animals than human beings. In contrast, modern sources often depict gnomes as diminutive, stout humanoids who wear tall, pointed conical caps and dress in solid colors such as blue, red, or green; in this depiction, the male gnome always has a long white beard. They have the intelligence of a human (are sometimes thought to be wiser), and have human-like personalities.
While their appearances may differ, the older and newer traditions do share a similar belief in gnomes' capabilities: They are said to move as easily through the earth as humans walk upon it, and the sun's rays turn them into stone. They are incredibly strong and fast, and said to possess almost supernatural abilities in the manipulation of natural material (although they also are said to fiercely guard against any unnecessary damage to the earth and wildlife).
From New World Encyclopedia