A synopsis is a summary of a longer text that includes information about its content, major elements or characters, themes or purposes, and method or style. A synopsis also includes a suggestion of the conclusion or ending of the longer text. However, because the purpose of a synopsis is to draw in readers, it should not be overly explicit in its revelations.
The primary purpose of a synopsis is to summarize a given text in a way that makes the reader want to read the whole text. Keeping that in mind, the writer should include a mention of the major elements or characters. If the synopsis is of a short story or novel, for instance, there should be a brief description of the protagonists, setting and main conflict.
This should be followed by a brief look at the major themes or main purposes of a text. If, for example, the synopsis is of an essay, the reader should be informed as to what is being investigated and for what purposes. In connection to this, the style or method of the original text should be discussed to shed light on how a topic is developed or how characters are brought to life.
Finally, the reader of a synopsis should be provided with a hint of where developments in the text lead. The writer should, however, be aware that the reader may lose interest in reading the longer text if too much is revealed.