Hawking news of the day goes back to ancient times. Hawking the death of "news as we know it" goes back 150 years.

Despite enormous changes in technology and content, Americans always have desired access to reliable, accurate and credible information, a habit not likely to change soon. But how people define and get their news changes often, sometimes in revolutionary waves.

The age of the Internet has left participants in the "old media" wary, worried and watchful. Predictions that this is the end of "news as we know it" send dire warning signals, as do the layoffs of newspaper journalists.

Since the mid-19th century, new technologies have regularly appeared -- and have led to new delivery systems for news. Eventually, the technologies and their impact on content and economics are "rationalized," and the various media keep some of their old roles and take on some new ones.

(Think of the beginning as the wild, wild West, where almost anything goes. Then civilization takes root and rational systems develop.)

In the 1830s, for example, presses that could handle rolls of paper instead of single sheets allowed publishers to print many copies cheaply. Publishers reacted quickly. Benjamin Day started the New York Sun, hired a reporter to cover the daily police-court sessions that focused on divorce and scandal, and sold papers on the street. His circulation soared to four times that of competing old-style political sheets. Hiring reporters to write about the intimate details of trials was considered scandalous, but the stories attracted a broader audience. Entrenched editors were forced to adjust or perish.

News as we knew it expanded to include the social as well as political, and it reported activities among more classes within society.

In the 1870s, editors had to cope with the advent of photo engraving, which allowed tabloids to run scandalous photographs on their cover pages. Not until the late 1880s did editors consider photographs valuable additions to newspapers, after Harper's Weekly used photos to expose corrupt Democratic party chairman Boss Tweed of New York.

News as we knew it had gone visual.

In the early 1900s, radio represented an entirely new medium. It was first viewed as person-to-person communication. Ham radio operators built crystal sets in their garages, and the U.S. Navy restricted use for ship-to-shore communications.

After World War I, corporate interests took over. They viewed radio as a mass medium and created news bulletins along with dramatic content. Newspaper owners were so fearful of this new development that they struck a deal with The Associated Press to bar radio owners from access to wire news. That reaction drove NBC and CBS to develop their own news departments. That development and competition from international wire services finally broke the lock on wire news. In 1939, polls indicated that 25 percent of the public relied on radio for news, and many listeners said they considered radio more objective than newspapers.

Now we could hear the news, not just read it.

Then came a dramatic rise in broadcast television. From 1946 to 1955, even though radio slashed its advertising rates as much as 25 percent, the big four radio networks' gross revenues declined by $32 million per year. But radio changed its tune, focused on music and survived -- with a little help from car radios and portable transistors.

Later, cable threatened television with the ability to deliver multiple channels.

Now we could see the news sliced and diced, however and whenever we wanted it.

The microcomputer and the advent of the Internet represented yet another new medium. Once again, people assembled the gizmos in their basements and garages and used them at first only as person-to-person communication.

Now people flock to the Web because of its vast capability for amassing and imparting knowledge, its instant communication capability, and its interactivity.

Now we can create the news, not just read it, listen to it or view it. We can report our own news on YouTube and blogs, bypassing the mediated news of reporters and editors.

This is a revolutionary period of transition in the media. It will remain so until business models are developed that fully address the incorporation of several media and until owners understand how audiences are segmented. Credible news sites such as www.nytimes.com, www.wsj.com and, on a local level, www.newsobserver.com will continue to attract readers. But new forms of media also are developing.

For example, (as I learned when my daughter became its word-of-mouth marketing manager) Voxant, the Viral Syndication Network, offers http://thenewsroom.com/, which warehouses information through contracts with credible news sources. This information then is made legally available to bloggers and others who want to "mash" the information to their own sites. The business model? Advertising follows the news that is "mashed" to the sites.

News outlets will have to learn how to perfect their sites, how to offer information that readers want online versus what they want in print. They will need to create new ideas for delivery and participation and new business models.

Newspeople can take comfort in history: We've been here before. No medium has died. Each reshapes, reconfigures, adapts, rationalizes and survives.