A polygonal shape is a flat, two-dimensional figure made up of straight line segments connected end to end. These line segments are called sides, and the points where they meet are known as vertices. Common examples of polygons include triangles, squares, and pentagons, each defined by the number of sides they have. Polygons can be classified as regular or irregular. A regular polygon has all sides and angles equal, like a square or an equilateral triangle. In contrast, an irregular polygon has sides and angles of different lengths and measures, such as a trapezoid or a pentagon with varying side lengths.