Sorcerers & Apprentices is a set of stories based in the real, modern world, except there are wizards. Unlike Harry Potter, there are less than 200 wizards world-wide, meaning that magical education is done on a personal, master/apprentice level. The prologue explains the world more fully.
The stories in this setting do not form a continuous narrative, but are basically excerpts from the lives of the main characters. They may not necessarily be in chronological order, or even the same format.