Search engine company Google has introduced an exclusive social network service called Google+.

Google has a low market share in the social networking market, though it had launched services like Orkut, Wave and Buzz in the past.

Google has tried twice before to make a foray into the social networking category. It launched Google Buzz in February 2010 and Orkut social network in 2004. But Buzz had to be withdrawn after privacy complaints from users, while Orkut failed to attract users in the important UK and US markets.

Google+ is the most ambitious move into social networking since co-founder Larry Page took over as chief executive of Google in April.

Google said it would give users "more ways to stay private or go public".

Google senior vice-president of engineering Vic Gundotra said, "We think people communicate in very rich ways."

"The online tools we have to choose from give us very rigid services."

Some of the key features of Google+ are: Circles – a functionality that allows individuals to place friends into groups; Hangouts – live multi-user video conferencing; Huddle – group instant messaging; and Sparks – a feature that connects individuals on the network to others with common interests.

"Online sharing needs a serious re-think, so it’s time we got started," Gundotra said.

"Other social networking tools make selective sharing within small groups difficult," she added.

Earlier this month there were reports that American pop star Lady Gaga has invested in a new start-up social networking service called Backplane, which is being funded by venture firm Tomorrow Ventures founded by Google chairman Eric Schmidt.

Google chief Eric Schmidt has admitted that the search engine company had missed out on the social networking opportunity.

He has said, "Four years ago, I wrote memos and I did nothing about those…CEOs should take responsibility. I screwed up."