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A perfect "brick-wall" filter in the frequency domain has a time domain transform of a sinc function, hence the name "sinc filter". This kind of filter is physically impossible to implement, but is often used in theoretical concepts.
There is another kind of filter called "raised cosine filter", which is physically realisable, and also has the desirable property of zero inter-symbol interference when used as a pulse shaping filter in communications. And the sinc function is actually an extreme special case of the raised cosine function.