Zemlyanka (Russian, Ukrainian: землянка, Belarusian: зямлянка. Czech: zemnice, Polish: ziemianka, Slovak: zemľanka) is a North Slavic name for a dugout or earth-house which was used to provide shelter for humans or domestic animals as well as for food storage. Based on a hole or depression dug into the ground, these structures are one of the most ancient types of housing known. Zemlyankas can be partially or fully recessed into the earth, with a flat roof covered with branches or sod, or dug into a hillside. The use of natural earth for insulation and protection for underground living has evolved into the "earth shelter" technology used today in architecture.