An investment in knowledge always pays the best interest.
Benjamin Franklin (1706—1790)
The style and form of printed writing is named typography. It includes typeface, point size, line length, leading, tracking and kerning (spacing between characters). Each one of these elements would be worth exploring individually. But for reasons of space, it is worth remembering that computers automatically take care of most of this.
There remain just three important decisions for you:
- Which font to choose?
- Which font size?
- How to structure the page?
Basically, there are two different types of fonts in Latin script: serif and sans serif. Serifs are these slight projections at the end of letters. They help the reader to identify letters much more quickly and make reading less tiring. This type of font is better for large bodies of text.
Without (French: sans) serifs you read more at a glance. Therefore, these fonts are also called poster type.
It should already be clear what we use each type of font for: serif types for books and other large bodies of text and sans-serif will be your choice for posters, headings and presentations (assuming that there aren’t large amounts of text on your slide!)
Within a single text there should not be more than two — or as an absolute maximum three — different fonts. Stay consistent!
The absolute minimum for a presentation is 18 pt – the bigger the better. Remember, slides are not your speaking notes, but combine a few key words with visual aids. Furthermore, if you target decision makers they may well be over 50 years old, and their eyesight might not be as good as it was.
Structure is there to provide orientation to your audience. When you introduce a new topic, you should make it as easy as possible to follow. You can easily define headings and body text by using distinct font type and size. For example, most of my presentations have 44 pt for the title, 36 pt for headings, 24 pt for text, and 20pt for subtexts and captions (in italics to make a difference).
Furthermore, you should structure your slides as you would in an essay. Instead of slide numbers, I would suggest placing the chapter titles on the top or bottom line. This means that latecomers or those who wake up from a nap (this often happens to me!) will be able to grasp where you are and what you are talking about.