In 1642, while still a teenager, he started some pioneering work on
calculating machines, and after three years of effort and 50 prototypes^[1]mechanical calculator. he invented the ^[2][3] He built twenty of these machines (called the Pascaline) in the following ten years.^[4] Pascal was a mathematician of the first order. He helped create two
major new areas of research. He wrote a significant treatise on the
subject of projective geometry at the age of sixteen, and later corresponded with Pierre de Fermat on probability theory, strongly influencing the development of modern economics and social science. Following Galileo and Torricelli, in 1646 he refuted Aristotle's followers who insisted that nature abhors a vacuum. His results caused many disputes before being accepted.
In 1646, he and his sister Jacqueline identified with the religious movement within Catholicism known by its detractors as Jansenism.^[5] His father died in 1651. Following a mystical experience in late 1654, he had his "second conversion", abandoned his scientific work, and devoted himself to philosophy and theology. His two most famous works date from this period: the Lettres provinciales and the Pensées, the former set in the conflict between Jansenists and Jesuits. In this year, he also wrote an important treatise on the arithmetical triangle. Between 1658 and 1659 he wrote on the cycloid and its use in calculating the volume of solids. Pascal had poor health especially after his eighteenth year and his death came just two months after his 39th birthday. Like so many others, Étienne was eventually forced to flee Paris because of his opposition to the fiscal policies of Cardinal Richelieu,
leaving his three children in the care of his neighbor Madame Sainctot,
a great beauty with an infamous past who kept one of the most
glittering and intellectual salons in all France. It was only when
Jacqueline performed well in a children's play with Richelieu in
attendance that Étienne was pardoned. In time Étienne was back in good
graces with the cardinal, and in 1639 had been appointed the king's
commissioner of taxes in the city of Rouen — a city whose tax records, thanks to uprisings, were in utter chaos.

In 1642, in an effort to ease his father's endless, exhausting
calculations, and recalculations, of taxes owed and paid, Pascal, not
yet nineteen, constructed a mechanical calculator capable of addition
and subtraction, called Pascal's calculator or the Pascaline. The Musée des Arts et Métiers in Paris and the Zwinger museum in Dresden, Germany, exhibit two of his original mechanical calculators. Though these machines are early forerunners to computer engineering, the calculator failed to be a great commercial success. Because it was extraordinarily expensive the Pascaline became little more than a toy, and status symbol,
for the very rich both in France and throughout Europe. However, Pascal
continued to make improvements to his design through the next decade
and built twenty machines in total.
MORE!https://en.wikipedia.org/wiki/Blaise_Pascal

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