This page on how to read an article history is intended as an aid to people who are researching with Wikipedia. Experienced Wikipedians often glean a great deal about articles from looking at the page history and following up to the individual edits that make up that history. This page describes some of these tricks of the trade.
The suggestions here apply mostly to substantive articles with a number of contributors. If the page history indicates that the page is entirely or almost entirely the work of one person, you are dealing with a situation more comparable to evaluating an article on someone's private web site.
First and foremost, the page history tells you something about who has worked on the page, and allows you to examine the successive versions of the article and the differences between them. Usually by looking through the edit history, you can quickly tell who has made substantive contributions to the article.