A quadrilateral is a polygon with four sides and four corners.
Quadrilaterals can also be called
quadrangles (similar to triangle) or
tetragons (similar to pentagon), though these names are not commonly used.
There are seven types of quadrilaterals, each with its own unique characteristics.
Any quadrilateral that cannot be described by any of these names does not take a special name; they are only called
The diagram above illustrates each of the types of quadrilaterals and their relationship to one another.