Therefore, abstracts should contain keywords and phrases that allow for easy searching.
In scientific writing, on the other hand, abstracts are usually structured to describe the background, methods, results, and conclusions, with or without subheadings.
Now how do you go about fitting the essential points from your entire paper— why the research was conducted, what the aims were, how these were met, and what the main findings were—into a paragraph of just 200-300 words?
To explore the role of the newspapers in the political events of the late First Empire, this dissertation analyzes all available newspapers published in Rio de Janeiro from 1827 to 1831.
Newspapers and their editors were leading forces in the effort to remove power from the hands of the ruling elite and place it under the control of the people.
Without an abstract, the search engine would be forced to search titles, which, as we have seen, may not be fruitful, or else search the full text.
It’s likely that a lot more than 60 dissertations have been written with those three words somewhere in the body of the entire work.
An abstract is not a review, nor does it evaluate the work being abstracted. Abstracts allow readers who may be interested in a longer work to quickly decide whether it is worth their time to read it.
While it contains key words found in the larger work, the abstract is an original document rather than an excerpted passage. Also, many online databases use abstracts to index larger works.
After reading the abstract, you can make an informed judgment about whether the dissertation would be worthwhile to read.
Besides selection, the other main purpose of the abstract is for indexing.