square: it has four square corners and four sides of equal length
rectangle: it has four square corners adn opposite sides of equal length
parallelogram: it has two pairs of parallel sides
quadrilateral: it has four sides
Some shapes have more than one name! A parallelogram is also a quadrilateral. A rectangle is a parallelogram and a quadrilateral. And a square is a rectangle, parallelogram, and a quadrilateral!