Two distinct planes intersect at a line, which forms two angles between the planes. Planes that lie parallel to each have no intersection.
In coordinate geometry, planes are flat-shaped figures defined by three points that do not lie on the same line. These surfaces having zero width infinitely extend into two dimensions. In Euclidean space, two discrete planes can only either cut across each other at a line segment or run parallel to each other without sharing any common points.
The angle formed between two intersecting planes is called a dihedral angle, which pertains to the interior angle formed when two adjacent planes meet. This angle is typically an acute angle, which is supplemented by an obtuse angle. The sum of the dihedral angle and obtuse angle totals 180 degrees. For two intersecting perpendicular planes, the angles formed measure 90 degrees each.