Form and Function
As a writer, you decide what goes into your summary based on what the summary needs to do for your readers. If you write a summary to remind yourself about the content of an article you read as part of a large research project, you'll decide about how much detail to include in your summary based on the scope and focus of your research. If you write a summary to include as part of a review of literature, you'll shape the summary based on how much you believe your target readers know about your topic before they begin reading your review of literature. A summary can be as short as a single sentence (a précis or nutshell statement) or as long as 30% of the length of the original article you're summarizing (a detailed summary). Choosing among the options for a summary means thinking about what your readers need.