In a cellular automaton, an oscillator is a pattern that returns to its original state, in the same orientation and position, after a finite number of generations.
The smallest number of generations it takes before the pattern returns to its initial condition is called the period of the oscillator.
An oscillator with a period of 1 is usually called a still life, as such a pattern never changes.
In Conway's Game of Life, oscillators had been identified and named as early as 1971.
[2][3][4] Additionally, until July 2022, the only known examples for period 34 were considered trivial because they consisted of essentially separate components that oscillate at smaller periods.