Mode

Mode is a statistical concept describing the most frequently occurring value in a data set. It is one of the measures of central tendency, alongside the mean and the median. In a finite sample, the mode is the value with the highest frequency. A data set can be unimodal (one mode), bimodal (two modes), or multimodal (more than two modes). If all observations occur with the same frequency, the data set has no unique mode. For continuous data, the mode is the point at which the probability density function attains its maximum; in practice, histograms or kernel density estimates are used to identify modes.

In probability theory, the mode of a random variable is the value that maximizes its probability mass or density function. The mode is not generally invariant to linear transformations, and it may differ from the mean or median. For symmetric distributions, mean = median = mode; for skewed distributions, the mode lies at or near the peak of the distribution.

Beyond statistics, mode has other uses. In computing and interfaces, a mode denotes a particular state of operation, such as edit mode or safe mode. In music, mode refers to a type of scale or tonal system (for example, major Ionian and minor Aeolian modes). The term derives from Latin modus, meaning measure or manner.