2D shapes, or two-dimensional shapes, are flat figures that have length and width but no depth. Common examples include squares, circles, triangles, and rectangles. These shapes can be found in everyday objects, such as a pizza (circle) or a book (rectangle). Each 2D shape has specific properties. For instance, a square has four equal sides and four right angles, while a triangle can have different types, like equilateral or isosceles, based on its side lengths. Understanding these shapes helps in various fields, including art, design, and mathematics.