Annotated Bibliography is a list of carefully selected sources according to a set of criteria for the purpose of identifying and evaluating research studies on a topic, their impact, focus, and research methodologies.
Annotated Bibliography is not only a summary of individual articles or books on a topic. While a short summary is necessary to introduce the work, it is the critical evaluation of the selected works that matters, how and why a work is different from other works on the topic, and how does a particular article or book advances the research on the topic.
Creating Annotated Bibliography is engaging with the research literature, both primary and secondary, in the topic of interest. It requires self-reflection and critical evaluation of the sources and is a building block in the process of writing a paper.