Steve had a thing for fonts which was one of the early differentiators of his creations. Though serif fonts are considered "friendly" and are used to increase readability, especially for large blocks of text (think magazine or newspaper article), sans serif fonts are thought by many to convey a contemporary or modern feel. Myriad is clean, has a high "x" height for friendliness and readability but is not as common as Arial or Helvetica. There are interesting variations in the line thicknesses and Myriad also has a wide variety of faces within the family.