Sine: a smooth, repeating waveform that oscillates around a central axis, defined by the mathematical function sin(x), where x is the angle in radians, and is characterized by its amplitude, frequency, and phase. 

Square:  is a periodic waveform that abruptly switches between two voltage levels (high and low) at regular intervals. 

Sawtooth: a waveform that rises linearly (like a ramp) and then drops sharply, resembling the teeth of a saw, hence the name. It’s characterized by both even and odd harmonics, contributing to its “harsh” or “buzzy” sound, making it useful in subtractive synthesis

Triangle:  a periodic, non-sinusoidal waveform characterized by its triangular shape, rising and falling linearly, and containing only odd harmonics, with higher harmonics decaying faster than in a square wave