How many equal sides does an equilateral triangle have?

An equilateral triangle is defined by all three of its sides being of equal length. This fundamental property sets it apart from other types of triangles, such as isosceles triangles, which have only two sides of equal length. In the case of an equilateral triangle, not only are all the sides equal, but all three interior angles are also equal, each measuring 60 degrees. This symmetry is a hallmark of equilateral triangles and is key to their unique properties in geometric principles. Thus, the correct answer indicates that an equilateral triangle has three equal sides, reinforcing its definition and characteristics.