👉 Periodicity is a property of a periodic system, such as a wave or a cycle, that means that it repeats itself in a set time interval. In other words, if you have a periodic system like a wave, the frequency (the number of times the system repeats) and the period (how long it takes to repeat one full cycle) are both constants. For example, consider the simple harmonic oscillator, which is an example of a periodic system with a constant frequency. The frequency (1