Music is no longer the number one way for young people to define themselves as they embrace social networks such as Facebook, according to an Australian survey released Monday.

Asked "What defines you?" the most popular response from young adults was "my friends", pipping music for the first time in the seven-year history of the annual Urban Market Research study.

"That came to us as a bit of a surprise," said Dion Appel, chief executive of the LifeLounge Group, which commissioned the survey of more than 1,750 Australians aged 16 to 30.

"What's not a surprise is the popularity of Facebook. But I suppose how that's influencing how young people actually define themselves is a pretty powerful insight.

"They are relying a lot more on friends to help define themselves."

Facebook was the number one website visited by those polled, with a massive 47 percent saying they spent five or more hours each week on the social networking site.

And while every young adult had at least one email address, this method of communication was on the wane, according to the study conducted with Sweeney Research.

Young adults associate email more with their professional or school life than their personal affairs and so prefer to communicate with peers via Facebook, text messaging, Skype and Instant Messenger, Appel said.

With a simple status update on their social networking pages, young people can "just put in how they are feeling and let technology deliver the messages" without needing to dig up people's email addresses, he said.

The research also confirms that most young people have a frantic digital life, with more than 80 percent "doing other things" while surfing the Internet or posting on social networks - like watching television or messaging.

But the barrage of information is also forcing youngsters to take some time out by "pressing pause" on the multimedia deluge, the survey said.

The most popular offline pastime was reading, with about 56 percent of those interviewed doing this for at least an hour a week. Cooking and going to art exhibitions were also popular.

"They are certainly not switching off. The one thing they claim they can't live without is the Internet. So what they are doing is just pausing momentarily and taking a breath," Appel said.

However he said social media were definitely on the rise.

"There are a number of ways for young people to get their kudos, or as we call it urban capital, and this is largely through social media now. They've got a voice that they can really properly broadcast in ways they have not been able to do in the past."