Tech moves fast! Stay ahead of the curve with Techopedia!
Join nearly 200,000 subscribers who receive actionable tech insights from Techopedia.
A logarithm (LN) is a concept in mathematics that denotes the number of times a number has to be multiplied by itself in order to arrive at a specified value. In mathematical terms, a logarithm of a number is the exponent that is used to raise another number, the base, in order to arrive at that number.
Logarithm is the reverse of the operation of exponentiation, which is raising a number according to a power. In exponentiation, a final value is determined after raising a base value with its exponent, while in logarithm, the final value and base are already known and the exponent is the value in question.
Logarithm is denoted as "logb (x) = r" or said as "the logarithm of x with respect to base b" or "the base-b logarithm of x," where b is the base, x is the value and r is the logarithmic value or the exponent.
So for example, if 23 = 8 is expressed in exponentiation because 2 × 2 × 2 = 8, the inverse of that, which is the logarithm of 8 with respect to 2 is equal to 3, expressed as log2 8 = 3. They essentially have the same meaning but are expressed in a different manner and order.
Logarithm is used in scientific and mathematical calculations in order to depict perceived levels of measurable quantities such as electromagnetic field strength, visible light and sound energy.