Abstracts are short (100-150 word) summaries of an article usually written by the article's author. They allow researchers to decide without reading the full article whether it is relevant to their research. Abstracts appear before the article's introduction and contain the following components, as applicable:
Abstracts cannot be written until the work has been written, because you can't summarize something that doesn't exist. Ask yourself: What did you do? How did you do it? What did you discover?
From Purdue OWL:
Minna, Autio. “Narratives of ‘Green’ Consumers – the Antihero, the Environmental Hero and the Anarchist.” Journal of Consumer Behavior 8.1 (Jan/Feb 2009): 40-53.
An annotated bibliography is a list of citations of books, articles, and other documents used in your research. Each citation is followed by a brief (usually about 150 words) descriptive and evaluative paragraph, the annotation. The purpose of the annotation is to inform the reader of the relevance, accuracy, and quality of the sources cited.
(Definition used with permission from How to Prepare an Annotated Bibliography by Olin Library Reference, Research & Learning Services, Cornell University Library, Ithaca, NY, USA)
When annotating a citation, structure it in the following format. You're not separating out the different parts of the annotation, but use this as a guide:
From University of Toronto New College Writing Centre:
McIvor, S. D. (1995). Aboriginal women's rights as "existing rights." Canadian Woman Studies/Les Cahiers de la Femme 2/3, 34-38.
This article seeks to define the extent of the civil and political rights returned to aboriginal women in the Constitution Act (1982), in its amendment in 1983, and in amendments to the Indian Act (1985). This legislation reverses prior laws that denied Indian status to aboriginal women who married non-aboriginal men. On the basis of the Supreme Court of Canada's interpretation of the Constitution Act in R. v. Sparrow (1991), McIvor argues that the Act recognizes fundamental human rights and existing aboriginal rights, granting to aboriginal women full participation in the aboriginal right to self-government.