Undoubtedly, a rectangle is a type of square.
A rectangle is a quadrilateral (a four-sided polygon) with opposing sides that are parallel and congruent (equal in length). A square has four equal-length sides and four right-angle intersections, making it a quadrilateral with opposite sides that are parallel and congruent. Since all of the angles in an equiangular rectangle, which includes a square, are equal, this type of rectangle can be thought of as having a special property.