Dan Rather signed off with his final CBS Evening News newscast as anchor with a single word that once earned him derision -- "Courage."

He dedicated the word to those affected by the terror attacks of Sept. 11, 2001, U.S. military personnel in conflict zones and those battered by the Dec. 26 tsunami and other natural disasters.

"To the oppressed or to those whose lot it is to struggle in financial hardship or in failing health; to my fellow journalists, in places where reporting the truth means risking all -- courage."

As he rose from the anchor's chair for the last time, members of his team gathered around him, giving him a round of applause.

Wednesday was the 24th anniversary of the day the 73-year-old Texan first sat in the anchor's chair, replacing the iconic Walter Cronkite.

Rather always cut a controversial figure. His aggressive style earned him the nickname "Gunga Dan" from his peers.

One memorable exchange happened in a news conference with former U.S. President Richard Nixon in 1974. Nixon asked him, "Are you running for something?" to which Rather snapped, "No sir. Are you?"

A live, on-air interview in 1988 with then-U.S. Vice-President George H.W. Bush degenerated into an on-air shouting match.

In an appearance on CBS's Late Night with David Letterman shortly after the Sept. 11, 2001 terror attacks on the United States, Rather started weeping.

And then there were "Ratherisms" such as:

• "This race is hotter than a Times Square Rolex."
• To John Kerry campaign official Joe Lockhart:  "I know that you'd rather walk through a furnace in a gasoline suit than consider the possibility that John Kerry would lose Ohio."
• "We used to say if a frog had side pockets, he'd carry a handgun."

And he was mocked for using "Courage" to end his broadcasts for a week in September 1986. He eventually abandoned the phrase.

CBS White House correspondent and former CTV reporter John Roberts says those quirks were just part of the package.

"He was lightning and a lightning rod. Bold men do bold things," Roberts says.

Actually, Roberts is rumoured to be in the running to replace Rather, along with Thalia Assuras, another CBS correspondent who began her career in Canada.

One version has the two sharing anchoring duties -- a move away from what some have called the "Voice of God" approach to presenting the news.

There's no question that traditional newscasts are in trouble. The audience's average age is 60. CBS's newscast was in third place of the so-called Big Three U.S. networks.

CBS suffered its own special crisis when a 60 Minutes II report on U.S. President George W. Bush's service in the Texas Air National Guard proved to be based on documents whose legitimacy was in question.

The story was considered so botched that it became the object of a special investigation. One person was fired outright and three others asked to resign.

Rather was the anchor of that episode. He personally apologized for the segment.

But his credibility took a beating. A Gallup poll conducted for CNN and USA Today found that only 23 per cent of people believed all or most of what Rather says, compared to 34 per cent in 2002.

Howard Kurtz, media writer for the Washington Post, said: "Dan Rather would not be retiring if it weren't for the fake memo scandal."

Rather will be continuing on as a reporter with 60 Minutes II. He's never lost his love for chasing a story.

His send-off hasn't all been laudatory. In recent days, Cronkite has said he thought Rather should have been replaced with Bob Schieffer, host of CBS's Face the Nation, years ago.

Schieffer will be the interim anchor until CBS names a permanent successor.

With a report from CTV's Tom Clark and files from The Associated Press