More and more Americans are choosing to get their news from sources that reflect their political viewpoints. While the tradition of non-partisan news reporting is still alive in the United States, studies show that the tradition is being challenged by cable networks and the Internet - sources of information that were not widely available just a decade ago.

It used to be that most Americans who were interested in what was going on in the world settled in front of their television sets at around 6:30 each evening and tuned in to one of the three national news broadcasts available on the airwaves. For more than 60 years, CBS, NBC and ABC have been providing Americans with news of the world. Their nightly programs still bear the mark of Edward R. Murrow, the legendary broadcaster who began his career in the 1930s and established honesty, integrity, and non-partisanship in reporting as the industry standard. Today, though, Americans are not always getting a mild-mannered, disinterested report when they tune in to the news. Instead, they often hear pundits yelling at one another about the issues of the day.

That is because viewers are not always tuning in to the standard network programs, the way they used to. Since 2000, the number of Americans turning to cable for their information has been on the rise, and a study conducted last year by the Pew Research Center for People and Press found that more Americans now get their news from the cable networks than from ABC, NBC and CBS. According to Carroll Doherty of the Pew Research Center, this is partly because the cable networks broadcast 24 hours a day, whereas a nightly newscast takes place at a scheduled time - and then is over. "People's lives have gotten busier, commuting times have lengthened over the years," Mr. Doherty says. "The idea of appointment television has declined, and (the networks) are feeling the pinch from that."

But there is a reason 2000 was the year cable news networks really started attracting audiences. That was the year the nation went through a very controversial, and very partisan, presidential election, and cable news programs tend to offer a lot more "opinion" than the nightly network newscasts. That opinion is reflected in the audiences tuning in to particular cable programs. The Pew study found that Republicans in particular have been turning to the Fox News Channel for their information, making the audience for CNN - an older cable network - decidedly more Democratic. "Some critics says Fox is tailoring its content in that way," Carroll Doherty says. "But it certainly is true that the frustration many Republicans and conservatives felt with CNN, in terms of political bias, has contributed to Fox's rise."

According to Carroll Doherty, the rise of cable news is linked to the growing politicization of American culture. But cable is not the only thing steering Americans away from the nightly network news. The Internet, too, has become an increasingly popular news source, especially for young people. It is now possible for someone in Biloxi, Mississippi, to read on-line editions of the New York Times, the London Telegraph, or even the Saudi Gazette.

But according to Scott Althaus, who teaches Political Science and Communications at the University of Illinois, Urbana-Champagne, Americans are using the Internet to filter the kind of news and information they receive. "Today it's so easy to set up a web page that identifies which particular news topics you would like to hear about, and you're going to hear about those, but you're not going to hear about others," says Professor Althaus. "To the extent that people are isolating themselves in news flows, they are going to potentially miss out on a lot of information that's floating out there, that's important, but it's not what they were looking for in advance."

The problem with that, according to Scott Althaus, is that if given a choice, people will gravitate toward entertainment news and partisan banter, rather than the hard-hitting economic, political and international news they need to make informed decisions in a democratic society. Still, says Professor Althaus, there is an upside to this proliferation of news media. He believes the breadth of opinion and information now available from network, cable and internet news services offers open-minded Americans a powerful opportunity to explore all sides of the issues behind today's news.