Space, space and a half, or double space?

None of the above! This is why we use leading instead of spacing. Spacing is old typewriter terminology. The three options listed above were the only ones available for typewriters. In almost every case (unless you are trying to mimic a typewriter) a single space is too close, a space and a half is too far, and a double space is ridiculous. Again, the focus has to be on readability.

Before we go on, another review of type speak is required: Point size and leading is expressed as 10/12 or 21/21.5 plus the alignment. This is pronounced ten on twelve or twenty-one on twenty-one and a half. In these cases, 10 and 21 are the point size and 12 and 21.5 are the leading in points. So, a common statement would be something like this: body copy is normally 10/12 justified left. This would be a paragraph with 10-point type and 12-point leading set justified with the last line flush left—like this paragraph and all the body copy in this book. When the point size and leading are the same, as in 16/16, it is referred to as being set solid. If the leading is less than the point size it is negative leading.

Leading is determined by font design, point size, line length, and reading distance. All fonts have differing built-in line spacing.

As you can see above, it proved that Futura has none and Bernhard Modern has a lot. Bernhard Modern also had a very small x-height. As a result, if we accept that normal body copy is 10/12 (and it is), then Futura should probably be set at 10/13 and Bernhard Modern at 15/15 or even much larger.

Some leading norms for normal reading distance:

• Tiny type: Type smaller than 7 point is usually set solid. With type set that small, you usually don’t want people reading it. It is used for the small type used to produce legalese [which no one reads anyway].
• Body copy: This is the normal reading copy in your documents. It is rigidly required to be 10/12 by traditional publishers, as mentioned. However, when you have the control, those figures should be adjusted by x-height and built-in line spacing. Larger x-heights require smaller point sizes. A large amount of built-in spacing between the top of the ascenders and the bottoms of the descenders in the line above takes less leading. Long line lengths require more leading. In general, bold, sans serif, or condensed fonts need more leading. This is your job: to figure out what reads best.
• Headers: Headlines and subheads are commonly set solid. The larger the point size used, the less leading is needed.
• All caps: Setting type in all caps often requires negative leading. This means that the leading is less than the point size. If you think about it, the reasoning should be clear. All caps have no descenders. Descenders are about a third of the point size. So headlines in all caps might well be set 36/28 or so.
  

Autoleading: One of the things you need to get under control is autoleading. The factory default is 120%. This means the leading will be 120% of the point size. This sounds good, and works well for body copy (10/12). However, it is disastrous for headers. I usually have the autoleading set at 105% (or less) for them. This is something you control in your paragraph styles on the Justification page.

An even worse problem with auto leading is seen when you drop in an inline or anchored graphic as a character in your paragraph: The autoleading adjusts to give room for the graphic. In these paragraphs, you will need to turn autoleading off. This also happens if you make a letter, a word, or words larger in a paragraph.

Related articles

• Anathema! Double spaces and double returns (hackberry-fonts.com)