Nut Graf

A nut graph is a paragraph that explains the context of the story. The term is also spelled as nut graf, nut 'graph, nutgraph, nutgraf. It is a contraction of the expression nutshell paragraph. In most news stories, the essential facts of a story are included in the lede, the first sentence or two of the story. Good leades try to answer who, what, when, where, why, and how as quickly as possible. The nut graf, which often will start in the third, fourth, or fifth paragraph, will explain any additional context for why the story is important. 

Nut grafs are sometimes not all 5ws are included in your news leads, or what you write might not explain the importance of the story, so you need a nut Graf to explain it in, well, a nut shell.
Nut grafs can be longer than one paragraph. Not all stories need nut grafs but it is frequently required or suggested in featured stories that don't definitive when, where, who, or why.