The purpose of an annotated bibliography is to present an overview of the published literature on a topic.
Different types of annotations serve different purposes:
Basicially, annotated bibliographies:
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A descriptive annotation provides a summary of the work.
Descriptive annotations may also be called summative annotations. These types of annotations do not evaluate the quality of the work, nor provide any statements on the relevance to your paper.
Descriptive annotations provide the following:
Descriptive annotations answer the following questions:
An evaluative annotation includes value judgments; it comments on the effectiveness of the work. Evaluative annotations are also called critical annotations.
Evaluative annotations answer the following questions:
A combination annotation includes elements of a descriptive and critical annotation--it summarizes as well as evaluates.