AP Lit stands for Advanced Placement English Literature and Composition. It is a rigorous English 4 level class for high school seniors, which is often but not always preceded by AP English Language and Composition (also called AP Eng or AP Lang for short) at the English 3 level during junior year.
My favorite class is AP Lit because I have been introduced to works of literature that have impacted my perspective on life, such as "Sonny's Blues" by James Baldwin. I enjoy how the reading selections are presented in a curated list that prepares us for the AP Exam while preserving the element of free choice so that students are interested in the works they read.
Lit is different than Lang because Lit includes far more works of fiction in different forms including plays, poems, short-stories, and novels. Lit is also different than Lang because of the increased workload. Although there is not the semester long project from Lang, there are about twice as many seminars and reading checklists. All of the work is still manageable, but students should take this into account. While Lit and Lang are not the same class by any means, Lit opens new doors into the realm of English. Students who did not take Lang should feel excluded from taking Lit, and those who succeed in Lang should feel good about their ability to do well in Lit.
For students who are not interested in Lit, the "Other Options" page talks about different paths.