Planck units represent a system of natural units derived from fundamental physical constants, namely the speed of light, the gravitational constant, and the reduced Planck constant. This system is used in theoretical physics to analyze physical phenomena across vastly different scales, offering a framework where the values of these fundamental constants are set to unity. By utilizing Planck units, dimensional analysis simplifies and potentially unifies concepts related to gravity, electromagnetism, and quantum mechanics. The inherent scales provided by these units define a characteristic length, time, and mass, often serving as a theoretical benchmark for the maximum possible energy density or the limits of physical predictability in certain quantum gravity models.