Logarithm taking
Taking the logarithm is an operation involving two numbers, the number x and the base b, and answers the question of what power the base b must be raised to in order to obtain x. It is written as blog(x) or logb(x). The name is derived from the Greek words logos (λόγος) and arithmos (άριθμός), meaning "proportion" and "number."2 ? = 8
? = 2log 8 = 3
? = 2log 8 = 3
The inverse (opposite) operation of taking the logarithm is exponentiation.
History

J. Burgius

J. Napier

H. Briggs
In 1614, the Scottish mathematician John Napier laird of Merchiston (1550 - 1617) was the first to publish tabulated values of the logarithm.
The English mathematician Henry Briggs (1561 – 1630) published in 1624 the logarithms of the natural numbers from 1 to 20,000 and from 90,000 to 100,000 for base 10 and calculated to 14 decimal places.
The gap between 20,000 and 90,000 was filled three years later by the Gouda surveyor Ezechiel de Decker (1603 - 1647).