While internet dating has not altered the nature of intimacy, it has fundamentally changed the way people initiate relationships, says Reis, a professor of psychology at the University of Rochester.

In conventional dating, a couple meet and get to know each other gradually, but online dating works by browsing computer profiles and relationship seekers often know a lot about their date before they meet.

The main benefit of dating websites is the instant access to hundreds, sometimes thousands, of potential partners beyond a person's typical social network, says Reis, whose study reviewed more than 400 psychological studies.

There are also advantages to making first contact via the internet, says co-author Paul Eastwick, as couples can carefully craft their communications and get ''off on the right foot''.

The danger lies when people spend too much time conversing over the internet and expectations for the first face-to-face meeting are not met, says Eastwick, from Texas AM University.

Online dating clearly has its pitfalls. The study found too many dating options overwhelm love seekers, and they often navigate away from people they would usually find appealing if given less choice.

Computer profiles also prompt people to ''shop'' for dates, focusing more on features such as physical attractiveness that become largely irrelevant once a relationship develops, says Eastwick, whose study is published in the journal Psychological Science in the Public Interest.

Not surprisingly, they also found ''modest misrepresentation widespread''. Many online dating sites claim to be able to unite a singleton with their perfect match based on sophisticated algorithms that assess compatibility based on everything from genetics to a pair's immune system.

But Reis and his team found no published evidence to support the claims by many websites that their matching capabilities are superior to traditional ''met-them-in-a-bar'' dating.