Sine wave
![The graphs of the sine and cosine functions are sinusoids of different phases.](/Images/godic/202502/11/Sine_and_Cosine.svg4624.png")
![](/Images/godic/202502/11/Animated-mass-spring4624.gif")
![Illustrating the cosine wave's fundamental relationship to the circle.](/Images/godic/202502/11/ComplexSinInATimeAxe4624.gif")
![Sine, square, triangle, and sawtooth waveforms](/Images/godic/202502/11/Waveforms.svg4624.png")
The sine wave or sinusoid is a mathematical curve that describes a smooth repetitive oscillation. It is named after the function sine, of which it is the graph. It occurs often in pure and applied mathematics, as well as physics, engineering, signal processing and many other fields. Its most basic form as a function of time (t) is: