Fourier transform

Fouriertransform is a method that transform a signal in time domain into a form that describes the frequencies present in the original function.

$\hat{f}(t)={\int }_{-\infty }^{\infty }x(t)e^{-i\omega t}dt$ This is a special form of the Laplace transform where the real part of the complex number $Re\{s\}=0$.