Literary criticism is the study, analysis, evaluation or interpretation of literature. It can be about one work, an aspect of one work, multiple works by an author, multiple works by different authors, and more. Most literary criticism is published in scholarly journals or in books.
There are a number of really effective ways to locate literary criticism, you just need to know a few tricks! This guide offers a variety of strategies for locating literary criticism on authors and/or works.
Keep in mind when you are researching that you may find other similar sources (plot summaries and biographical works) that can be useful, but are not criticism.