the logarithm with the constant e as the base is called the natural logarithm, denoted as ln^N(N>0).

its meaning is the limit value that can be achieved by continuous doubling of growth per unit time.

the base e of the natural logarithm is given by an important limit. we define: when x goes to infinity, lim(1+1/x)^x=e.

e is an infinite non-repeating decimal, its value is approximately equal to 2.718281828..., it is a transcendental number.