Quadrilateral

A quadrilateral is a shape with four sides and four angles. You know what sides and angles are right? Well, think about a square or a rectangle, those are both kinds of quadrilaterals! A square has all four sides the same length and all four angles the same measure (90 degrees). But a rectangle has two pairs of sides that are the same length, and four angles that are all 90 degrees.

Now, there are also other types of quadrilaterals that aren't squares or rectangles. Some of them have only one pair of opposite sides that are the same length, like a parallelogram. And some have only one pair of opposite angles that are the same measure, like a kite.

But no matter what kind of quadrilateral you're looking at, it always has exactly four sides and four angles. So if you ever see a shape with four sides, you can call it a quadrilateral!