Square A four sided polygon. A square has all sides same length and all angles on a square are 90 degrees.
Rectangle A square that has four 90 degree angles but all four sides do not have to be the same length. A square is a rectangle but a rectangle isn’t a square.
Trapezoid Like a rectangle but all angles don’t have to be 90 degrees. A rectangle is a trapezoid but a trapezoid is not a rectangle. A square is a trapezoid but a trapezoid id not a square.
Parallelagram Like a Trapezoid but the sides must be parallel. Ex. Left must be parallel to Right and Top must be parallel to Bottom. Square is a parallelogram but a parallelogram is not a square. A rectangle is a parallelogram but a parallelogram is not a rectangle.
Circle A line that is the same distance in every direction from one point inside the plane that the circle is in. The point is in the direct middle of the circle.