A unit of measurement in type setting used primarily for designating type size and line spacing. There are 12 points to a pica, and approximately 72 points to an inch. Type size is measured from the top of an ascending letter to the bottom of a descending letter. (See Pica).
The number of points from the top of the ascender to the bottom of the descender. Sometimes the point size is given in dots or pixels, and in other instances, it is given as how many points (or units of 1/72nd of an inch) the font will have when the characters are printed on paper. Thus, if the characters in a font are, on average, 1/2 inch high when printed, the font is said to have a "point size of 36" or to be a "36 point font."