Introduction to Exponents and Logarithms

Logarithmic functions and exponential functions are inverses of each other. That is, they undo each other. 

The logarithm of a number is the exponent by which another fixed value, the base, has to be raised to produce that number.

Any positive number can be used as the base of a logarithm but certain bases ($10$, $e$, and $2$) have more widespread applications than others.

Logarithmic and exponential forms are closely related, and an equation in either form can be freely converted into the other.