Wikipedia:Summary style
World War II ... was a global war that was underway by 1939 and ended in 1945 ....
The start of the war is generally held to be 1 September 1939 ....
World War I radically altered the political map, with the defeat of the Central Powers ....
The Second Italo–Abyssinian War was a brief colonial war that began in October 1935 and ended in May 1936 ....
Germany and Italy lent support to the Nationalist insurrection led by general Francisco Franco in Spain ....
It is advisable to develop new material in a subtopic article before summarizing it in the parent article. (An exception to this is when the subtopic is non-notable; see below.) For copyright purposes, the first edit summary of a subtopic article formed by cutting text out of a parent article should link back to the original (see ). Templates are available to link to subtopics and to tag synchronization problems between a summary section and the article it summarizes.
Articles over a certain size may not cover their topic in a way that is easy to find or read. Opinions vary as to what counts as an ideal length; judging the appropriate size depends on the topic and whether it easily lends itself to being split up. Size guidelines apply somewhat less to disambiguation pages and to list articles, especially if splitting them would require breaking up a sortable table. This style of organizing articles is somewhat related to news style except that it focuses on topics instead of articles.
This is more helpful to the reader than a very long article that just keeps growing, eventually reaching book length. Summary style keeps the reader from being overwhelmed by too much information up front, by summarizing main points and going into more details on particular points (subtopics) in separate articles. What constitutes "too long" is largely based on the topic, but generally 40 kilobytes of readable prose is the starting point at which articles may be considered too long. Articles that go above this have a burden of proof that extra text is needed to efficiently cover their topics and that the extra reading time is justified.
Sections that are less important for understanding the topic will tend to be lower in the article, while more important sections will tend to be higher (this is news style applied to sections). Often this is difficult to do for articles on history or that are otherwise chronologically based, unless there is some type of analysis section. However, ordering sections in this way is important because many readers will not finish reading the article.
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