In the world of political science and its literature, it can be difficult to tell what material is legitimate and a worthwhile read and what, put plainly, is not.

Political science professor Michael Berkman said he tries to read professional and "journalistic" writings to inform himself about the 2008 presidential candidates.

"All things are not created equal," Berkman said of books in the political genre.

Berkman provided several tips for deciding whether or not political literature is worth reading. He suggested researching the authors and making sure established journalists have authored the books.

He said to keep in mind that there are many "ideological" books written for a narrow public.

He added it's also important to remember some public opinion is shaped by the elites, some information comes from commercials and some comes from the Internet.

Some information, from both parties, is "pure conspiracy," he said. One example, in his opinion, is Jerome Corsi's The Obama Nation: Leftist Politics and the Cult of Personality.

The point of books like Corsi's is to get the ideas out into the media stream through the Internet and cable television because they're already "written to the chorus," he said.

Berkman said to look for the "other kinds, not written just to be read by the already converted."

Here is a selection of literature written by and about the presidential candidates that offers readers an honest and useful look at both Barack Obama and John McCain:

'The Audacity of Hope,' by Barack Obama

Obama's New York Times bestseller The Audacity of Hope was published in 2006 and reflects the senator's views on topics like race, religion, family and politics. He includes anecdotes from his childhood and his more recent political life.

In Michiko Kakutani's review of the book from Oct. 17, 2006, Obama is an "elastic, personable voice that is capable of accommodating everything from dense discussions of foreign policy to streetwise reminiscences."

He also described the candidate as authentic and regular. In his own words, Obama explains the book's topic as "how we might begin the process of changing our politics and our civil life."

Kakutani continues by explaining that Obama may not know the perfect method of how to achieve this goal through plans, charts and maps, but he presents suggested challenges and routes for "the ways we can ground our politics in the notion of a common good."

'McCain: The Myth of a Maverick,' by Matt Welch

Matt Welch takes the standpoint in McCain: The Myth of a Maverick that Republican presidential candidate John McCain's background is significantly unexplored, at least from a journalistic approach.

Therefore, with this work, he took it upon himself to do the research, and in McCain he presents a "user's guide" introductory format with only the informative background facts that contribute to his purpose. He doesn't particularly bash the senator, nor does he overly praise him.

McCain glances at some of the senator's inspirations from his youth, including Ernest Hemingway, specifically his novel For Whom the Bell Tolls.

In the book, Welch said the senator is most affected by "the utter romantic hopelessness of it all."

One of the "myths" the author explores is that McCain is a "man of the people." In Welch's opinion, McCain would rather deal with a few deep-pocketed supporters than thousands of small donors.

Welch states repetitively McCain enjoys having his "back up against the wall" and "sticking defiantly to his guns."

'Hard Call,' by John McCain and Mark Salter

In his co-authored book with Mark Salter, Hard Call: Great Decisions and the Extraordinary People Who Made Them, McCain takes a look at people throughout history who had to make tough decisions and the outcomes that prevailed.

Ronald Reagan, Harry Truman and Abraham Lincoln are three of the 20 historical figures profiled, according to the Los Angeles Times in an Aug. 13, 2007, review by Matt Welch.

Interwoven into these tales are McCain's "presidential ambitions" which, according to New York Times reviewer Jacob Heilbrunn, form the book's landscape.

In the first chapter, the authors describe the questions one should evaluate before making a critical decision, including the risk factor, time frame, preparation, level of confidence and knowledge of involved persons.

One hard call Welch said McCain is "unwilling to show his hand about" is the one about the war in Iraq, which Welch dubs "the hardest presidential call of them all."

"Ability to evolve and adapt," by Kevin Fagen for the San Francisco Chronicle

In his article on Sept. 14, San Francisco Chronicle reporter Kevin Fagan said Obama has an ability to evolve, and he "intensely educates and redefines himself at key junctures in his life."

The article examines some of the candidate's history pre-election. Part of the background tells the story of Obama as a young black man "itching to live on the mainland" to determine who he should be as an adult.

Fagen also explained Obama's activism in Chicago as a community organizer and how, in combination with a trip to Africa, the young man "learned at last what it meant to be African-American."

In the article, Fagen said after three years at Harvard Law School, Obama was "ready to build his next identity: politician."

The article's summary of his political years isn't extensive, skimming through achievements and citing a few quotes by fellow politicians.

Mostly, Fagen characterizes Obama as different and said "he would not be at the threshold of history today if he did not possess that ability to adapt."