Why finding impluse response is important?

[spark360z]

I've been studying about signals and systems.

My question is on any systems why we always want to know the impluse response?

I know that impluse has infinite amplitude and it has the same magnitude in all frequency range but why is that important?

sin&cos signal also have the same amplitude in all frequency range. This is confused me a lot.

I may misunderstand something.

 

[LvW]

I've been studying about signals and systems.
My question is on any systems why we always want to know the impluse response?

I don't think that it is "important" to know the impulse response of a system. And I do not "always want to know" the impulse response.
However, it is interesting to realize that the impulse response (time domain) has a certain relation to the frequency domain (inverse Laplace transformation of the transfer function).
More important is the step response (time domain) and the transfer function (frequency domain).

 

[crutschow]

The impulse response is an easy way to get the overall frequency response of the system using Fourier analysis.

 

[LvW]

The impulse response is an easy way to get the overall frequency response of the system using Fourier analysis.

Yes, but is this an "important" method? Is it used in practice?