Unlike the way most other encyclopedias were printed, World Book has traditionally been published in variously sized volumes, depending on the letter of the alphabet. Although most volumes cover exactly one letter completely, the letters with exceptionally numerous entries ("C" and "S") are divided between two volumes, while adjacent letters with relatively few entries ("J"–"K", "N"–"O", "Q"–"R", "U"–"V", and "W"–"Z") share a volume.
