What is the interior angle of a pentagon?

The measurement of an interior angle of a pentagon depends on whether the pentagon is a "regular pentagon". The sum of the measures of the interior angles of any polygon can be calculated using the formula (n-2)180, where n = the number of sides. If the pentagon is a regular pentagon, then all of the interior angles are congruent (i.e. : 144 degrees).

Interior angle is the inside angle of any angular object. A triangle for instance has three outside angles and three interior angles, the angles of the points from the inside.