Aliasing and Folding

Aliasing	This movie illustrates the phenomenon of aliasing. A 600 Hz sinusoid is sampled at 500 samples per second.
Folding	This movie illustrates the phenomenon of folding. A 600 Hz sinusoid is sampled at 750 samples per second.
NO Aliasing	This movie illustrates that the Sampling Theorem is true. In this case, a 600 Hz sinusoid is sampled at 2000 samples per second. Since the samples are taken at more than two times the frequency of the cosine wave, there is no aliasing.