Or you always need to have all 6 variations? Specifically in this paper we examine the benefits of good typography and find that good typography induces a good mood. Research has shown that different letter spacing, stroke sizes, and x-height can have a positive effect on the readability of different sizes of text. An optical family contains styles specifically optimized for each size and use case - rather than trying to be one-size-fits-all, like many of the typefaces common on the Web. Banner should be used in point sizes of 18 and larger and is meant for lighthearted short texts or headlines. He would generate results and tabulate them, and find very good graphic ways of expressing why this was better than that.
