Sorry to be off-topic here, and
PLEASE don't mind me for being a stick in the mud (and feel free to roll your eyes at me, everyone!), but I'm speaking strictly as a typography nerd here - the definition of
kerning (according to Wikipedia) is "the process of adjusting the spacing between characters in a proportional font." Strictly speaking, it is typically used for typesetting, whether it be physically setting lead type on a printing press the old-fashioned way, or doing it on the computer. in calligraphy terms, it is generally referred to simply as "letter spacing." Leading, which is also used commonly in typesetting, is used to refer to the spacing in-between lines. In the old days, printers would put in pieces of lead in-between the lines, so that is where "leading" comes from. In a calligraphy setting, it is referred to as "line spacing."