A summary is basically a recap or breif exploration of something. So if you were summarizing a book you would explain who the main character is, who the antagonist is and give a short explanation as to what the protagonist did to stop the antagonist.
Short example:
Mary had to steal the book back from the bad guy before he used it to destroy the Earth. She snuck around his base and eventually got to the main room where she had to fight the bad guy and escape with the book before his henchmen could catch up.
Explanation:
Jordan Baker hates Tom Buchanan but works tirelessly to really get Daisy separated from him, at least for a short time, by facilitating Daisy's relationship with Gatsby. Tom, while ignorant that Jordan is operating toward him across his back, doesn't really like Jordan but feels he could use herself.
This question refers to the article "Do Juvenile Killers Deserve Life Behind Bars?" by Nina Totenberg.
In this article, Totenberg discusses whether life in prison is too harsh a punishment for juvenile killers. The author does not take a position on this matter, and instead focuses on presenting arguments that describe both sides of the question. The main purpose of the author is to encourage readers to think about the subject because legislation needs to be passed soon, and this is a difficult question that deserves consideration. She shows how important this matter is when she says:
<em>"Two years ago, the court used the same rationale when it struck down the penalty of life without parole for nonhomicide crimes committed by juveniles. But in Tuesday's cases, the court faces the question of life without parole in homicide cases... the big question before the Supreme Court on Tuesday is whether life without the possibility of parole is itself an unconstitutionally cruel and unusual punishment when it is applied to juveniles."</em>
