Filtering is easier to describe in the frequency domain than in time.

Evidence

Equations A1.9 and A1.10 are known as the Fourier transform pair and can be used on any type of signal, whether periodic or nonperiodic. Together, they form a powerful basis for analyzing and processing signals, in particular, because it is easier to consider filtering in the frequency domain rather than the time domain. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2766

Categorization

• DEFINE: Names the Fourier transform pair and states its universal applicability to signals.