The concept of poles and zeros in filters was introduced to me during our lab (our lab isn't sync with our lecture) through the pole-zero plot generation of filters in MATLAB. I didn't get its importance until it was mentioned in our lecture that poles make the equation infinity (or its denominator zero) while the zeros make the roots in the numerator zero. I still can't quite grasp what poles and zeros are. Can someone give an an intuitive and simple explanation on what poles and zeroes are? Much appreciated.