To discover what symmetry is, take a piece of paper, fold it, and cut out a shape along the fold. Unfold the shape that you cut out. This figure is symmetric. That means it is exactly the same on both sides of the crease. The crease is called the line of symmetry.
Some figures have one line of symmetry.
Many others have more than one line of symmetry. The examples below show some figures and their lines of symmetry. Many things in the world around us have symmetry. Here are a few examples we found.