Similar figures are shapes that have the same form but may differ in size. This means that their corresponding angles are equal, and their sides are in proportion. For example, if you have a small triangle and a larger triangle that both have angles of 30°, 60°, and 90°, these triangles are considered similar. To determine if two figures are similar, you can compare their corresponding sides. If the ratios of the lengths of the sides are the same, the figures are similar. This concept is often used in geometry and can be applied to various shapes, such as triangles, rectangles, and circles.