Box projection is also known as cube mapping. It's an extension of XYZ to UVW mapping, where the projection of the cube's planes is based on the normal direction of the surface. This projection provides a quick way to texture objects without too much distortion, however seams may be visible between the projection planes. Image textures are mapped to the (-1, -1) - (1, 1) range.
Transform - The transformation applied to the projection. Accepts a Transform node.
Coordinate Space - The coordinate space used by the projection.