One of the two main types of
manga distributed in the U.S.A. It refers to manga marketed to
girls, as opposed to Shounen, which is aimed at boys.
People often assume that all Shojo is romance, but though this is usually the case, it is not always so.
In essence, the differnce between Shojo and Shounen is that while in Shounen the characters exist to further the plot, in Shojo the plot exists to further the characters.