Boxer Library
An abstract is a concise summary of the contents of your article. Within 300 words or less you should be able to convey the key points of the article including a short summarized version of your methods and findings. The purpose of an abstract is to give the reader a snapshot of the full articles, enticing them to read the full one. Another way to think about it is like a movie trailer for an article. Many researchers use the abstract as a tool for deciding if they want to do a more in depth analysis of the article, or review other articles. If an abstract is not written well, readers may overlook the article even if it is relevant to their information need.
At the very least the abstract must include:
When thinking about creating an abstract, think of ABC: 
Accurate: You only want to include information that is in the article itself. Do not add supplemental information not included in the full article. Doing so will only confuse the reader, and hinder the evaluation of your article.
Brief: Keep things concise and brief. Abstracts are made to be short, and to the point. Remember people may only spend a minute or two reviewing your abstract, and they will base their decision to read the article on the content of your abstract.
Clear: Make sure your article is free of jargon especially if being published in a journal outside your particular field. Also define acronyms the first time you use them as to not confuse the reader.
The only way you should cite an abstract is if the full text of the article is not accessible. What this means is the full text does not exist at any location anywhere in the world, not just the Boxer Library. In these situations the abstract citation should be an additional piece of evidence and not a core one that your paper is based on. If you cannot find the full text of a particular article and want to cite it, please email eresources@rosalindfranklin.edu, and the librarians can verify if full text exists. Remember if the library does not have the full text, you can always place an Interlibrary Loan Request where the library will request a copy of the article from another library at no cost to you.
Since the abstract is a snapshot of the article in 300 words or less, you will not be able to properly evaluate the article for it's content or quality. There were situations where someone cited the abstract and misinterpreted the data because the whole article was not read. Being such a concise format, there may be points relevant to your specific information need that are not included in the abstract.
There are a few types of abstracts with different purposes.
This type of abstract is made to list the different parts of the study. In this type of abstract you will be required to include information from the study parts such as purpose, methodology, results, and conclusions. These abstracts are really easy to read, because they give the reader a real sense of the whole article. After reading the abstract, the reader should want to read the full article, and analyze it for quality. Most articles use this abstract format.
This type of abstract is typically less structured than informative ones. This type of abstract summarizes the purpose and methods, but may not include the results and conclusions. By not including this information the abstract does not make judgments, and is more of an outline than an overall summary. These abstracts are usually 100 words or less.