What makes rock legend Tom Petty such an icon of cool, an artist on the same level as the likes of Keith Richards?

It's the raw nature of the sound of his band the Heartbreakers, the character of his voice and, perhaps most of all, his laconic Southern presence, according to Warren Zanes, author of Petty: The Biography.

"He's not going to be the first guy to start shooting his mouth off," said Zanes. "He's going to sit at the back of the room, take it all in and then come in with the line that kills everybody."

Zanes, a former guitarist with the Del Fuegos, was handpicked by Petty to chronicle his rise from humble beginnings in Gainesville, Fla., to his induction into the Rock and Roll Hall of Fame. Over the course of his career, Petty has sold more than 80 million records worldwide, making him one of the best-selling music artists of all time.

And while Petty and his Heartbreakers continue to be one of the best known and longest-running American rock groups, Zanes notes that when they were getting started, a crowded musical marketplace kept the band's debut album off the U.S. charts. In fact, Petty and his crew gained popularity in Britain before picking up momentum in the States thanks to a persistent promoter named John Scott.

"After they broke in England, he just went out on a one-man mission to radio, and he broke that record," said Zanes. "If you took him out of the equation, it's hard to say what would have happened -- no matter how good that first record was."

It was not until Petty's third album, "Damn the Torpedoes," went platinum that he became a household name.  The album, which sold nearly two million copies, includes the now classic singles "Don't Do Me Like That," "Here Comes My Girl" and "Refugee." It was also produced by Jimmy Iovine, who co-founded Interscope Records, and is now better known as the man behind Beats Electronics (acquired last year by Apple (AAPL - Get Report) ) and business partner to rap star Dr. Dre.

"Jimmy Iovine and Tom Petty had ambitions that matched one another," said Zanes, adding that Iovine had a golden ear, and noting that his ability to approach the material as an engineer rather than a musician helped lift the recording sessions.

Zanes also explained how Petty, like most musicians starting out, signed a Faustian deal with his original label, only to be forced to fight it in court later on when his sales took off and the money started rolling in. Separately, Petty also fought with Heatrbreakers drummer Stan Lynch over the decades until the battles became too heated and Lynch left the band.

"Petty often had issues with Stan Lynch, feeling like he just wasn't coming to the song with what he needed Stan to bring to it," said Zanes. "It turned Stan into an object of concern for Petty, but at the same time Stan was the great cheerleader in that band. He was the extrovert in a band of introverts."

Another big cheerleader for Tom Petty and the Heartbreakers was Fleetwood Mac star Stevie Nicks. Nicks and the band performed together on the hit "Stop Draggin' My Heart Around." The vocal chemistry between the pair had many fans wondering if there was something more to the relationship than a hit single.

"He went so far with me as to say 'We had our times,'" said Zanes. "But he wanted to leave it at that."