An isosceles triangle is a type of triangle that has at least two sides of equal length. The angles opposite these equal sides are also equal, which gives the triangle its unique properties. Isosceles triangles can be found in various shapes and sizes, but they always maintain this characteristic of having two equal sides. These triangles are often used in geometry and design due to their symmetry. The height of an isosceles triangle can be drawn from the vertex opposite the base, creating two right triangles. This height helps in calculating the area and understanding the triangle's dimensions better.