An abstract is an especially terse summary, usually of a report or an article.  A well-prepared abstract contains enough information to be considered a highly condensed version of the entire paper.

In a report or professional journal, the abstract gives readers a quick, brief, reliable overview of contents.

When it accompanies an article, the abstract is often included in electronic databases and becomes an important reference tool for future researchers.

An abstract forces both reader and writer to analyze the contents  and methodology of a paper very carefully.

A good abstract will convey the main point and the structure of a paper.  It will make clear exactly what each part contributes to the whole.  Therefore, it is best written after the paper is completed.

Typically, an abstract is written as a single well-organized paragraph.  Most abstracts are approximately 250 words long.

1. Any material not in the text, including figures, tables, or references.
2. Comments on how to follow specific methods or use apparatus.
3. Literature references.

The objectives and purposes of the study.

1. The materials, methods, techniques, apparatus, and their uses, as well as new items and new uses of  standard techniques and equipment.
2. Scientific and common names or organisms.
3. Specific drugs, biochemical compounds, etc., including manner of use and route of administration.
4. New theories, terminology, interpretations, or evaluations--all stated very concisely.
5. New terms and special abbreviations and symbols defined.

1. Statement of problem, question, or hypothesis to be investigated.
2. Description of methods, including participants, procedures, and materials.
3. Synopsis of support drawn from literature, data, and sound reasoning.
4. Description of results.
5. Discussion of the significance of the results.

Some of this information is drawn from Arthur W. Biddle and Daniel J. Bean, Writer's Guide:  Life Sciences.  Lexington, MA:  Heath, 1987.