A scalene triangle is a type of triangle where all three sides are of different lengths. This means that none of the angles are the same, making each angle unique. Because of this, scalene triangles do not have any lines of symmetry, which sets them apart from other triangles like isosceles or equilateral triangles. In everyday life, you can find scalene triangles in various objects, such as certain types of roofs or in the design of some road signs. Understanding scalene triangles is important in geometry, as they help us learn about different shapes and their properties, which can be applied in fields like architecture and engineering.