What is a line symmetery?

Line symmetry, also known as reflectional symmetry, occurs when a shape can be divided into two identical halves that are mirror images of each other along a line, called the line of symmetry. If you were to fold the shape along this line, both halves would match perfectly. Common examples include a butterfly's wings and certain geometric shapes like squares and circles. The concept is fundamental in geometry and art, highlighting balance and proportion.