What is an acute angle?

An acute angle is defined as an angle that measures less than 90 degrees. This classification is fundamental in geometry and distinguishes acute angles from other types of angles, such as right angles, which are exactly 90 degrees, and obtuse angles, which exceed 90 degrees but are less than 180 degrees. The precise measurement of acute angles plays a crucial role in various mathematical concepts, including the study of triangles, where all angles in an acute triangle are acute. Understanding this classification is essential for solving problems related to angles in various geometric contexts.