Line symmetry, also known as reflection symmetry, occurs when a shape can be divided into two identical halves that are mirror images of each other. The line that divides the shape is called the line of symmetry. For example, a butterfly or a heart shape exhibits line symmetry, as each side mirrors the other. In geometric figures, common examples of line symmetry include circles, squares, and triangles. A shape can have multiple lines of symmetry; for instance, a square has four lines of symmetry, while a rectangle has two. Identifying line symmetry helps in understanding the balance and proportion in various designs and patterns.