What is a quadrilaterral?

A quadrilateral is a four-sided polygon characterized by four edges (sides) and four vertices (corners). The sum of its interior angles is always 360 degrees. Common types of quadrilaterals include squares, rectangles, parallelograms, trapezoids, and rhombuses, each with its own specific properties. Quadrilaterals can be classified based on their sides and angles, making them a fundamental shape in geometry.