A review on recent generalizations of exponential distribution

These distributions have been widely used to analyze lifetime data, on account of its analytical tractability, also used in physics, queueing theory, and hydrology, often used to model the reliability of electronic systems, which do not typically experience wear-out type failures. Exponential variables can also be used to model situations where certain events occur with a constant probability per unit length, such as the distance between mutations on a DNA strand, or between road kills on a given road.