a cirsquare
straight and curved
Two shapes are congruent if they have the same shape. This includes the corresponding angles, straight and curved lines.
If it is a closed figure which doesn't cross over itself (like a bowtie looking figure), then it is called a polygon.
A simple straight line.It join two vetices(corners) of a polygon(a closed figure made of straight lines).
Cylinder - a solid figure formed by two congruent parallel circles joined by a curved surface.