Rdio, pronounced Ar-dee-o, is offering free, on-demand streaming music in the hopes of winning customers.

The San Francisco-based start up company that competes with Spotify and Pandora is introducing its free digital on-demand music service with no registration, no downloads and no ads. Consumers are tuning in already, making Rdio a top Alexa search term on Thursday, as the company has no catch and no tricks for now -- just free online music.

Competitors including Spotify and Pandora offer free digital music, but it comes with advertisements. To get music without advertisements on those services, users have to pay a fee. Rdio hopes to launch its service for free, for now, and later convert those users into subscribers for its unlimited desktop and mobile-music plans that cost from between $5 and $10 per month, the company said.

Rdio was started in August 2010 by Skype co-founder Janus Friis. Rdio, located at www.rdio.com, promotes on its Web site Unlimited Music Everywhere, and Choose what you want to play and listen as much as you want -- from the web or your phone. No ads.

Free music with no ads is very distinct from what everyone else is doing, Drew Larner, chief executive officer of Rdio, told Bloomberg in an interview. We know when people use Rdio they get hooked. That's the bet we are making.

While Rdio must invest heavily to provide the free music, compensating record companies and artists for music played, the company said the free service will be available for a significant time, Larner said. It's all about the effort to successfully launch the service against established competitors.

Once people get in the door, we've found they love our service, Larner told Fast Company. But getting people in the door is the challenge. We believe this will result in getting a lot more people to use Rdio, and hopefully get a lot more people to convert and pay. So we're putting our money where our mouth is.

Rdio users can share music through social networks like Facebook and Twitter, the company said. Competitors including Mog and Spotify also announced integration with Facebook last month -- something that allows users to easily share, post and discuss music.