The surface of the lake against the background of a snow-covered forestThe surface of the lake against the background of a snow-covered forest
Reflection of the bright sky in the smooth surface of the night riverReflection of the bright sky in the smooth surface of the night river
The rays of the setting sun gliding across the water surfaceThe rays of the setting sun gliding across the water surface
В математике: граница, отделяющая геометрическое тело от внешнего пространства. Наружная сторона чего-н..