1) The document discusses different types of polygons, including their definitions, properties, and classifications. It defines polygons and their key elements like sides, angles, and diagonals.
2) Polygons are classified based on factors like the number of sides, whether the shape is convex or concave, and if the sides and angles are equal or not. Common polygons from triangles to dodecagons are identified along with their properties.
3) Formulas for finding the number of triangles formed by diagonals of a polygon and the sum of interior angles are provided based on the number of sides. Different ways polygons can be further classified are outlined.