The arithmetic triangle was developed in 1653 by Blaise Pascal. He named this triangle after himself and today it is known as Pascal's Triangle. It is an arrangement of certain whole numbers in a triangular pattern.

Blaise Pascal was regarded as a brilliant man of his own time. He made contributions to science, mathematics, and religious philosophy. Pascal was born on June 19, 1623 in Clermont-Ferrand of central France. His father was a highly placed civil official and everyone expected Pascal to follow in his footsteps.

But Pascal proved to be a child prodigy. At the age of twelve, he figured out the proposition of Euclidean geometry with no help. At the age of seventeen, he wrote an essay on conic sections which contained a theorum that was named after him.

Pascal also invented many things. He constructed the first digital calculating system for his father. He invented the syringe and the hydraulic press.

He also established the principle of hydrostatics, known as Pascal's law. This law says that in a fluid at rest in a closed container, a pressure change in one part of the fluid is transmitted without the loss of every portion of fluid and to the walls of the container. It also says that the pressure at a point in the fluid at rest is the same in all directions.

The arithmetic triangle was known about long before Pascal's time. Omar Khayyam used it in 1100 and Chu Shih-Chieh of 1303 included it in a Chinese manuscript. European mathematicians used it one hundred years before Pascal during the development of science and algebra.