The first thing we are going to do, before entering fully into the establishment of the meaning of the term quadrilateral, is to determine its etymological origin. In this sense, we can say that it is a word that emanates from Latin, the word "quadrilaterus" that can be translated as "having four sides." She, in turn, is made up of two distinct parts:
• "Quadri", which comes from "quattuor" and is synonymous with "four."
• "Latus", which means "side".

Quadrilateral is a concept which is used to name what you have four sides .

We must bear in mind that within the scope of geography, the term quadrilateral is now used. Specifically, there is talk, for example, of what has been called the Quadrilateral of Bohemia, which becomes a space determined by four mountain cores and that in the past came to form what was the historical border of the Countries Czechs

Those four mountainous groups are the Metallic mountains, the Bohemian jungle, the Sudet mountains and the Giant mountains.

Its most frequent use is in the geometry . A quadrilateral, in this sense, is a polygon whose sides are four. This means that the quadrilateral is determined by four segments that make it up.

Having four sides, all quadrilaterals also have two diagonals, four vertices and four interior angles. These characteristics remain beyond the shape of the quadrilateral, which can vary.

The squares , the rhombuses and the rectangles , for example, they are quadrilaterals: they have, therefore, four sides, four vertex, four internal and two diagonal angles. However, it is clear that the shape of these three geometric figures is not identical.

What varies in the quadrilaterals with respect to its shape is the arrangement of its sides; the points to consider to establish a quadrilateral classification is the parallelism of its sides, as well as the length of each and its interior angles. Based on these variables, it is possible to distinguish between the following types:

* parallelogram: its opposite sides, that is those whose vertices do not touch, are parallel;

* square: It is the simplest figure of all, both when making calculations on it and drawing it, even for people who do not have specific knowledge of geometry or mathematics usually. All sides of a square are the same, as are all their interior angles (which are 90 degrees and are called straight) and its diagonals (which not only coincide in their measure but are perpendicular to each other). Finally, the square is a figure belonging to the group of bisectors, which means that it can be divided into two equal parts, and has circumference inscribed, that is, it is internal and tangent to each of its sides;

* rhombus: It is similar to the square, since it also has its four equal sides, but its interior angles are not straight, but two are sharp and two are obtuse, and each pair coincides in measure. Their diagonals, on the other hand, are different, being one greater than the other, although they are also perpendicular to each other. The rhombus, as well as the square, is a bisector and has an inscribed circumference;

* rectangle: its parallel sides, those that do not share vertices, are equal to each other. In the same way as the square, its interior angles are straight and all its diagonals measure the same, although in this case they are not perpendicular to each other, given the differences in their sides. Its circumference, unlike the previous figures, is circumscribed, which means that it is external and passes through all its vertices, instead of being tangent at his sides;

* rhomboid: its two minor sides and its two major sides are equal to each other;

* trapeze: only two of its sides are parallel and can be rectangle (one of its sides is perpendicular to its bases, two of its internal angles are straight, one obtuse and the other acute), isosceles (its non-parallel sides measure the same, it has two acute angles and two obtuse equal to each other) or scalene (its four internal angles are different).

Outside of geometry, it is known as quadrilateral at boxing ring and to other spaces destined to host a fight with ends sports. As you can guess, the quadrilateral has four sides, which are delimited by ropes, fences or other materials. For example: “The Uruguayan boxer promised that he will end up standing in the ring”, "The jaw hook threw the American out of the ring", “If you are afraid, you cannot go up to the ring”.

Among the most important rules that boxers must meet within the ring include:
• The size of the ring must be at least 7.3 meters on the side.
• Each round has a time of 3 minutes.
• Waist down strokes are not allowed.
• If a boxer falls, he must get up without anyone's help within a maximum period of ten seconds in order to continue the fight.

Do not forget that in the city of La Laguna, Quadrilateral is the name of the most important nightlife area. It is made up of all kinds of bars, discos, pubs ...