Metallic ink, shiny paper, enlargements, and brilliant colors enhance publications, slides, and filmstrips. But, too much of a good thing makes blurry and tiring images for older eyes. Identification is the ability to recognize specific images. In printing, the size and detail of the image depends on the choice of font and spacing. Choose a font that's large enough to be seen clearly, and simple enough that the smallest letters are crisp and clear.
Decorative type is difficult to read.
The white space within and surrounding a letter or image is equally important. More internal white space increases legibility. Always use proportional spacing, where the white space between letters is kept constant regardless of letter width. Serif type best meets these requirements. The spacing between lines of type also increases readability.