Anamorphic widescreen, when applied to DVD manufacture, is a video process that horizontally squeezes a widescreen image so that it can be stored in a standard 4:3 aspect ratio DVD image frame. Compatible playback equipment can then re-expand the horizontal dimension to show the original widescreen image.
Anamorphic widescreen is also a term to describe widescreen films projected using an anamorphic lens on the projector. The film is printed in 1.37:1 format, but the picture is "squashed together", with everything on it looking elongated vertically, as in a fun house mirror. The anamorphic lens on the projector corrects the picture so that the images on the screen look normal.
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