In this post, the central point of the topic is quadrilaterals, which are the foundations for beginning the study of geometry. The history of quadrilaterals dates back to ancient times, with the famous Greek mathematician Euclid being one of the first to study their properties. The pioneering geometers in the study of quadrilaterals were Thales of Miletus (c. 624 – 546 BC), Pythagoras of Samos (c. 585 – 500 BC), Euclid of Alexandria (c. 365 – 300 BC).