KERNING PAIRS. I have posted on fonts, but I have never understood them. I did look at the back page of every book I read that was published by Knopf, which always identified and gave the history of the font the book was printed in, but I never noticed the differences between the characteristics of the fonts. An article by Jason Fagone in New York magazine (June 2 to 8) about a legal dispute between two leading font designers gave me an idea of some of the subtleties that I don’t perceive. (One of the designers is said to be able to “look at a printout of a letter form and see whether it is one pixel off.”) Fagone refers to “kerning pairs”. I looked up “kerning” in this wikipedia entry and found that kerning is “the process of adjusting the spacing between characters in a proportional font, usually to achieve a visually pleasing result”. This discussion at About.com says that “kerning pairs” are “commonly kerned pairs of letters with the spacing already adjusted for best visual appearance so that manual kerning of headlines and subheads is unnecessary”.
I posted here that I am indifferent—from an esthetic point of view—as to whether there is one space or two spaces between sentences. I don’t notice the spaces between letters any more than I notice the spaces between sentences.