** Euclid**

He was born in mid 4th century BC. Euclid was given a name Euclid of Alexandria to distinguish him from Euclides of Magara who was a Greek mathematician.

Euclid's works were most popular in the history of mathematics. Until the late 19th century, his writings were used in mathematics textbooks. Most famous Euclidian geometry is solved by deducting Euclid theorems.

Euclid also worked on some concepts like perspective, spherical geometry, number theory, and rigor. From very little things we know about his life, he was most probably born in 325 BC. All of his birthplaces and others mentioned were not sure since it happened ages ago.

Elements :

Euclid's accomplishments helped to present elements in a single, logically coherent framework which makes it easy to use and for reference purpose. At the earlier times, no book mentioned that elements are from his accomplishments. They say that they are from lectures of Theon.

Proclus is the only proof that Euclid has written some thoughts about elements. This is most famous for geometric results. It was also known that the elements also includes number theory. To differentiate this system from the non-Euclidean theory introduced in the 19th century, this system is now often referred to as Euclidean Geometry.

Fragments :

In the second book of Elements of Euclid, the Papyrus Oxyrhynchus is a fragment. This fragment was unearthed by Grenfell and Hunt in 1897. T.L.Heath classically translated this as follows :

" If a straight line is to be cut into equal and unequal segments, then the rectangle contained by the unequal segments of the whole together with the square on the straight line between the points of the section needs to be equal to the other half. "

Other works of Euclid :

Other than these works, few additional works have survived to the present days. Some of them are :

- Data
- On the division of figures
- Catoptrics
- Phenomena a treatise on spherical astronomy
- optics

** Usage**

Geometry is usually needed to be considered as a branch of Mathematics. It is so because it added lots of beauty to mathematics. It concerns with the questions of shape, size, the relative position of figures, and the properties of space.

**Geometer**

Geometer is a person who works in the field of Geometry. Geometry exists from the early days which are helpful for calculating lengths, areas, and volumes. Some of the generalized concepts have evolved which are more or less similar to geometry. These include points, lines, surfaces, angles, and curves. Geometry concepts are applicable not in mathematics but also in art, architecture, as well as for other branches of mathematics too. Contemporary includes many subfields. Some of them are as follows :

- Euclidean Geometry
- Differential Geometry
- Topology
- Convex Geometry
- Algebraic Geometry
- Discrete Geometry
- Computational Geometry