Podcasting, a new type of Web broadcasting via digital music players like the Apple iPod, might prove a boon for businesses that are increasingly catching on to its novel commercial potential.

After making its debut in Japan around late 2004, podcasting, or distribution of sound files, has grown in popularity at an impressive speed.

Programming on offer includes news, music, language lessons, interviews, book readings and comic performances.

Meanwhile, radio broadcasters, facing a decline in ratings, are pinning their hopes on podcasting to revive their operations. Some firms are already sanguine about prospects for their new businesses.

"Podcasts can capture narrower sectors of the audience that cannot be reached by the radio," said Yukihiro Okada, head of program production at FM Inter-Wave Inc.

Some companies are meanwhile eyeing podcasts as a promising advertising medium.

Podcasts have captured a wide audience since Apple began distributing iTunes in Japan last August. It is a free software program that allows users to download and transfer audio files onto iPods.

People are now able to register their favorite weekly radio programs on their computers in advance so the computers automatically record the programs.

The recorded files are transferred to users' iPods, who listen to them wherever they like.

Radio companies have been quick to embark on new podcasting services.

In August, local radio firm IBC Iwate Broadcasting Co. became Japan's first AM station to release podcasts. Besides airing local news, the company promotes local culture by, for example, teaching listeners words and expressions unique to the local Hanamaki dialect, which is spoken in Iwate Prefecture.

The number of registered listeners using the company's podcasts already exceeds 10,000.

"Listeners are increasing at a far faster pace than we anticipated," said Kensuke Joji, an official with IBC Iwate's digital service division.

Even people living outside Iwate, including those residing abroad, have signed up for the service, boosting the company's advertising revenue, Joji added.

While many radio broadcasters are reworking existing programs to make them more suitable for podcasts, FM Inter-Wave, a broadcaster of foreign-language programs, is producing original podcasts, including live performances of jazz bands and interviews with Japanese and foreign celebrities.

Radio companies are hopeful that the advent of podcasts will help them expand their customer base, breathing new life into their businesses to arrest the ongoing fall in advertisement revenues.

According to the nation's largest advertising agency, Dentsu Inc., radio stations' ad revenue slid to some 180 billion yen in 2004 from 210 billion yen in 2000 as the number of listeners declined.

Other companies are trying to cash in on the promise of podcasts as an advertising medium.

Major Internet access provider Nifty Corp. went into the online ad business, placing ads via podcasts starting in January.

The company debuted its Podcasting Juice Web site in July. It displays a list of podcasts that can be downloaded.

Because the site has proved popular and customers tend to listen to a long run of podcasts at a time, the company plans to insert commercials at the beginning and end of each program.

"We intend to step up our marketing efforts to achieve ad revenue of 100 million yen in the year ending in March 2007," said Takashi Narita, an official with Nifty's ad division.

The phenomenal success of the iPod has so transformed the entertainment scene that it might create further, unanticipated spinoffs that could pave the way for companies to enter new types of online businesses.