Fourier transform of non periodic signal

1. Can Fourier transform be used for non-periodic signal?
2. Can a non-periodic function Fourier series?
3. Is Fourier transform always periodic?

Can Fourier transform be used for non-periodic signal?

Fourier series is defined for periodic signals and the Fourier transform can be applied to aperiodic (occurring without periodicity) signals.

Can a non-periodic function Fourier series?

Fourier series can only represent functions that are periodic. However, non-periodic functions can be handled using an extension of the Fourier Series called the Fourier transform which treats non-periodic functions as periodic with infinite period.

Is Fourier transform always periodic?

It is worth noting that the discrete time Fourier transform is always 2π periodic, while this is not the case for the continuous time Fourier transform. Also, both the continuous time and discrete time Fourier transforms are defined in the frequency domain, which is a continuous domain.