This document discusses various types of angles including right angles which are 90 degrees, acute angles which are less than 90 degrees, obtuse angles which are greater than 90 degrees, vertical angles which are angles opposite each other when two lines intersect, supplementary angles which are two angles whose measures sum to 180 degrees, complementary angles which are two angles whose measures sum to 90 degrees, and linear pairs which are two angles whose non-shared sides are opposite rays.
