If you’re writing a document that you will need to print and hand out (report, memo, newsletter, etc.), The AdWeek Copywriting Handbook offers you this counterintuitive but fascinating insight:
In tests of the legibility of printed documents, serif fonts (like Times New Roman, fonts with decorative loops and strokes at the ends of letters) win over san-serif fonts (like Arial, with no decorative extra strokes). And they win big.
In fact, tests find that readers have five times greater comprehension with documents written in serif fonts.
The lesson: If you want to make your document easier to read and digest for your readers, use serif fonts.
Related lesson: If you need to read an important work-related document yourself, and you plan to read it in hardcopy format rather than on the screen, make sure it’s in a serif font. If it isn’t (if it’s a Word document using a sans-serif font like Arial, for example), convert it to a serif font before you print it out.