👉 A posttrapezoid is a quadrilateral with two pairs of parallel sides. It's also known as a trapezium or a trapezoid with one pair of opposite sides being parallel and the other pair being non-parallel to it. This type of quadrilateral can be thought of as a type of parallelogram, but it has its own unique properties and characteristics. The posttrapezoid is named after the French mathematician Auguste Perret, who was
