# How to distinguish between the different frequency domains?

Sometimes the terms 'Fourier domain', 'complex frequency domain', 'Frequency domain' and 's domain' are used interchangeably.

For Laplace transforms, "s domain" will work as well, and I do believe they are interchangeable. I do not believe "Fourier domain" would be correct usage in this case. "s domain" may be preferred if you wish to emphasize that real values of $s$ have a clear aperiodic interpretation (exponentials in the time domain).