Measuring Type

There are two basic units of measurement in typography: points and picas. There are 12 points in a pica and 6 picas in an inch. Type is measured in points; the line length, or measure, is measured in picas.

To understand how we arrive at the point size of type, let's examine a piece of type: it is a rectangular block of metal with a printing surface on top. The block is called the body and the printing surface is called the face.

The height of the body is.918" and is known as type-high. Although this dimension is not important to the designer, it is very important to the printer that all type be exactly the same height in order to print evenly and consistently.

The width, which is called the set width, is dictated by the width of the individual letter, the letters Mand W being the widest and 1 being the narrowest.

The depth, known as the point or body size, is the dimension by which we measu re and specify type.

Type comes in many sizes, the most popular typefaces ranging from 5 point to 72 point. Type sizes 14 point and smaller are called text types, those larger are called display types.