5   Page and Screen Design

Typefaces and Type Sizes

The two main classes of typefaces are serif typefaces and sans serif typefaces. Most typefaces clearly belong in one class or the other. Serifs are the small extensions at the ends of letters and are widely believed to make them more legible, and the text faster to read.

While you probably have many typefaces to choose from, most manuals use only two typefaces: a serif typeface, such as Times Roman, for the text, and a sans serif typeface, such as Arial, for headings.

Most people using Microsoft Windows simply select from the TrueType typefaces that were installed when they installed Windows. TrueType typefaces have both printer and display fonts so that what you see on the screen is virtually identical to what you get from the laser printer. As well, if others print out the file on different laser printers, they’ll get the same typefaces as long as they installed the TrueType typefaces when they installed Windows.

Figure 5-8: Examples of TrueType typefaces

The normal type size for text is from 10 point to 12 point. This is the size we are most used to reading, and therefore we read it the fastest. If you are writing for the visually challenged, younger readers, or where the text may be read at a distance, you may need to increase the type size of the text to 13 point or 14 point. Type smaller than 10 point is much harder to read and noticeably slows down readers.

You may want to use a slightly larger typeface for online manuals. Most monitors, including high-resolution monitors, aren’t as sharp and clear as print on a page. As well, many people view their monitors from a greater distance than they would read a book.

On the Web, type size is not specified directly, but is set relative to the base font. For example, headings can be set as +1, +2, or +3, while text can be set as 3 (base font), -1, -2, or -3. Remember that the size of the base font can be modified by the user but usually defaults to approximately 12 point.