The base-10 logarithm, often written as log10 or simply log, is a mathematical function that determines the power to which the number 10 must be raised to obtain a given value. For example, if log10(100) equals 2, it means that 10 raised to the power of 2 equals 100 (10² = 100). This function is widely used in various fields, including science, engineering, and finance, to simplify calculations involving large numbers. Base-10 logarithms are particularly useful for dealing with exponential growth or decay, as they can transform multiplicative relationships into additive ones. This property makes it easier to analyze data, such as in pH calculations in chemistry or measuring sound intensity in decibels. Understanding base-10 logarithms is essential for interpreting many scientific and mathematical concepts.