Related: [Similar uses of Taylor Series and Fourier Series](https://math.stackexchange.com/questions/2884280) ***AND*** [Connection between Fourier transform and Taylor series](https://math.stackexchange.com/questions/7301) ***AND*** [Is Fourier series an “inverse” of Taylor series?](https://math.stackexchange.com/questions/47430) ***AND*** [On the vector spaces of Taylor Series and Fourier Series](https://math.stackexchange.com/questions/424955).
– Dave L. RenfroNov 18 '18 at 10:05
The proposed duplicate target emphasizes *connections* between a power series and a Fourier series representation, while the present Question (terse as it is) asks about how we "use these differently". I'm going to withhold voting to close until the OP has a chance to weigh in on this aspect.
– hardmathNov 18 '18 at 15:13