Interesting Math History

Question :
What does 'e' stands for in arithmetic ?

Answer :
e is the base of the Napier or Hyperbolic system of logarithms.
e = 2.71821828459045.
It is a unique real mathematical constant. In 1618 John Napier published the first references to the constant in the table of an appendix of a work on logarithms.
In 1690 and 1691 the first known use of the constant, represented by the letter b.

In 1727 Leonhard Euler started to use the letter e for the constant and the first use of e in a publication was Euler's Mechanica in 1736.

'c' was also used by some researchers but e was more common and eventually became the standard.

The reason of using e may be the first letter of word 'exponential' is e.