Typesetting measures are units of measurement used in the printing industry to determine the size and spacing of text and images. EMS (3 letters) stands for 'em-size', which is a unit of measurement equal to the point size of a particular font. PICAS (5 letters) is a unit of measurement equal to 12 points, and ENS (3 letters) stands for 'en-size', which is a unit of measurement equal to half of an em-size.