A bibliography is a list of sources on a particular topic. Put together, an annotated bibliography is a list of sources on a topic that offers a summary for each source.
What is an annotated bibliography?
An annotated bibliography is a list of citations (or references) for books, articles, documents, etc: all the sources used for your research, with an accompanying paragraph that describes, explains and/or evaluates each entry in terms of quality, authority and relevance.
What is included in the summary part of an annotated bibliography?
Your summary should include the following elements:
(1) a sentence or two that describes the author's credentials, purpose, and audience.
(2) a brief summary of its content, and is this source answering the research question; clarifying your understanding of the research; reviewing the literature of the research, etc.
(3) a sentence at the end of the summary that explains its value to the student.
Your professor may require some variation of standard APA-style annotation. Two examples are illustrated below.