what are plane shapes

Plane shapes are two-dimensional geometric figures that exist on a flat surface, known as a plane. They have only length and width, with no depth or thickness. These shapes are the building blocks of geometry and are extensively studied in mathematics. Some examples of plane shapes include triangles, squares, circles, rectangles, ovals, polygons, and other curvilinear figures. These shapes are characterized by their boundaries, which can be made up of straight sides or curved lines. The straight lines that make up a plane shape are called sides, and the points where two sides meet are called corners or vertices. Different plane shapes have different attributes, such as the number of sides or corners. For example, a triangle has three sides and three corners, while a square has four sides and four corners. Plane shapes can be open or closed, with closed shapes having a complete and continuous boundary that forms a closed loop.