Having a huge network of online friends does not mean you have any more close friends than the rest of us, a British researcher has said.

Social networking sites like Facebook and MySpace are changing the nature of how people connect by making it easy to collect hundreds of friends and acquaintances online.

"Our data suggests weak ties are (more common) but there is no difference in the number of close friends people have," said Will Reader, an evolutionary psychologist at Sheffield Hallam University.

"Nearly all our close friends require face-to-face contact," Mr Reader told a meeting sponsored by the British Association for the Advancement of Science.

The researchers focused on Facebook and MySpace, two of the most popular sites where millions of people express themselves online with personal photographs, musings and other content while adding "friends" to their network.

In their study, Mr Reader and colleagues asked people a series of questions about their attitudes toward friendships and found 90 per cent of individuals said it was imperative to know somebody face-to-face to form the tightest bonds.

The key it seems is face-to-face interaction where people can interpret social clues such as laughs and smiles that help determine if others are friends to be counted on, Mr Reader said.

"That weird experience of laughing together where people can find they have similar goals and experiences is necessary," Mr Reader said.

"It is a bit like a dance between two scorpions where one is wondering if the other is going to eat me or sleep with me."

Other studies have shown most people have about 150 people in their extended networks, with just a small number considered a member of the inner circle of close friends, Mr Reader said.

Even when people's social networks ballooned into many hundreds or more than a thousand people, the number of close friendships did not change, he said.

"One of the possibilities is that changing the nature of these networks can decrease the cost of maintaining friendships," Mr Reader said.

-Reuters