Typefaces, fonts and leading

Which typeface should I use?

If you ask ten designers which typeface to use you will probably get at least nine different answers. If there was a definitive answer all books would look the same. So you need to choose a typeface (Times, Garamond etc), a font (the point size) and the leading (the space between the lines of type).

As an example, a designer’s specification might be 11/13pt Times
11pt – is the font
13pt – indicates 2 points of extra space or leading (more explanation later)
Times – is the typeface

Microsoft uses a percentage value for the leading which can be misleading. But they also have an option for a specific point value.

The origin of these archaic terms might help you understand them better.

The font, or size of the typeface
This was governed by the block that each letter was carved from (wooden type), or cast from (metal type). The blocks for every letter had to be the same overall size and this is the point size – not the actual size of the bit you see.

You can see in this illustration that we have a ‘cap height’, an ‘x height’ and the block size, or point size of the typeface. But not all typefaces appear to be the same size even though they may all be 12pt.

type slug or block

In this illustration you can see the difference in what is called ‘appearing size’ between three classic typefaces which are all chosen as the same point size.

typeface appearing size
Different type faces

The leading, or space between each line of type
The distance between each line of type is called the ‘leading’ because originally thin strips of lead were inserted between slugs of type (a whole line of type) to add space between them and make the text more legible.

leading in metal type

Microsoft, in their infinite wisdom, decided that this was too much for their users so they offer as default 1, 1.5, 2 etc as their spacing options between lines of type. But Microsofts default of no extra space (i.e. 1) puts somewhere between 1.17% and 1.25% of space depending on your version of Word and the operating system you use. You can over-ride this by setting a specific leading and I have explained this here.