An annotated bibliography describes the field of research on a topic and should include sources that reflect the range of approaches to the subject.
There are four main types of annotations.
Descriptive
A descriptive (also called an indicative) annotation gives a brief overview or summary of the text. This can include a:
Evaluative
An evaluative (also known as a critical) annotation includes an analysis of the work. In addition to a summary of the essential ideas, it provides judgments—negative, positive, or both—about their quality. This kind of annotation usually begins with broad comments about the focus of the source, then moves to more details, and then to your evaluative comments. Some useful points to consider are the:
Informative
An informative (also called summative) annotation also provides a summary of the source. Unlike the indicative annotation, however, it gives actual information (hypothoses, proofs, other data) about the source. It contains no statements about the source's relevance to your paper or critical remarks evaluating the source's quality. An informative annotation includes the author's:
Combination
Most annotated bibliographies are a combination of the above, and include one or two sentences summarizing or describing content, in addition to one or two sentences providing an evaluation.