How many sides does a triangle have?

A triangle is defined as a polygon with three edges and three vertices. This geometric figure is one of the simplest forms of polygon and is characterized specifically by its three sides and the angles formed at the vertices. Each side corresponds to one of the angles, and the sum of the internal angles in any triangle is always 180 degrees.

The uniqueness of a triangle lies in its properties, such as the ability to determine the shape and size of the triangle based on the lengths of its sides and the measures of its angles. Triangles are foundational elements in geometry and are used extensively in various applications, including engineering, architecture, and art.