Which type of triangle has no sides equal?

A triangle with no sides equal is classified as a scalene triangle. In a scalene triangle, all three sides have different lengths, which leads to all three angles being different as well. This property distinguishes it from other types of triangles.

An isosceles triangle has at least two sides that are equal in length, while an equilateral triangle has all three sides equal. A right triangle is defined by having one angle that measures 90 degrees but may or may not have sides of different lengths. Therefore, the unique characteristic of the scalene triangle is that it has no equal sides, making it the correct answer.