In typography, setting type with letters over and under one another, in a variety of orientations. One particularly undesirable form of vertical setting is vertical stacking:
Sometimes vertical setting is used with regular horizontal type arrangement for attention-getting purposes. It is best to use only one (short) line, not several.
Another common site of vertical setting is a standard book edge. For book spines, the type is set in the downward direction. Thus, when the book is flat on a table with its cover up, the type on the spine can be read easily. (In Europe, book spines are commonly printed in the up direction.)