sentences:  Condensed versions of the full Schaum's Outlines called "Easy Outlines" started to appear in the late 1990s, aimed primarily at high-school students, especially those taking AP courses.These typically feature the same explanatory material as their full-size counterparts, sometimes edited to omit advanced topics, but contain greatly reduced sets of worked examples and usually lack any supplementary exercises.As a result, they are less suited to self-study for those learning a subject for the first time, unless they are used alongside a standard textbook or other resource.