Rotational symmetry is when a shape can be rotated around a central point and still look the same at certain angles. The number of times a shape matches its original position during a full rotation determines its order of rotational symmetry. This concept helps identify symmetrical properties in various objects.

In Class 6 Maths Chapter 9 on Symmetry students learn about lines of symmetry where a figure can be divided into two identical parts. The chapter also covers reflection symmetry where one half of the figure is a mirror image of the other and helps identify shapes with different numbers of lines of symmetry.