Base

The number an exponent is "attached" to (what a leech) in its superscript. In a logarithm, it's located in the subscript (the number below the log).

Common Logarithm

A logarithm with a base of 10. It's usually written all sneakily without a base as log x, but sometimes it shows up as log₁₀ x.

Exponential Decay

The ever-decreasing quality of an exponential function with a base b that's in between 0 and 1.

Exponential Function

A function with the x in the exponent over a constant base, which grows or decays depending on the value of the base. Coefficient optional, like mayonnaise.

Exponential Growth

The ever-increasing quality of an exponential function with a base b > 1.

Inverse Function

Given a function f(x), the inverse function f ^-1(x) is a new function where the input and output values are swapped. Translation: (a, b) becomes (b, a) for every single point on the graph.

Inverse Operation

A symbol that reverses the original operation, given the same input. Think about adding 2, then subtracting 2.

Logarithmic Function

A function containing a logarithm, which rises quickly at very low values of x and then puts on the brakes hard to slow down at higher values of x.

Logarithmic Scale

A graphing scale that increases at an exponential rate. It's usually recognizable by tick-marks at powers of 10 and weird googly eyes attached.

Natural Logarithm

A logarithm with a base of e, often written as ln. Contains no preservatives.

Operation

A way, usually represented by a symbol, to manipulate one or more input numbers and create one or more outputs. Addition, subtraction, multiplication, division, exponentiation, and logarithms are all operations. Not the board game, and definitely not surgery.