The social networking giant Facebook has made its ambitious move into email, mounting a head-on challenge to Google, Hotmail and other services and attempting to turn its website into the centre of users' online communications.
The company is to start offering Facebook.com email addresses to its 500 million users, and launching what it called a "social inbox" which will pull together emails, instant message conversations and text messages from users' friends and contacts, both from within Facebook and from outside the site.
"This is not an email killer. This is a messaging system that includes email as one part of it," Facebook's founder, Mark Zuckerberg, told attendees at the launch in San Francisco yesterday.
The aim of the service is to encourage users to spend as much time, and to share as much information, within Facebook, where the company can make money from selling personally targeted ads.
It is also aiming to simplify the way people exchange messages online, so that they don't have to keep switching between inboxes for email and messages. "We don't think a modern messaging system is going to be email," Mr Zuckerberg said.
In particular, it is being tailored for youngsters who prefer texting and instant messaging to the more formal medium of email. "Talking to high-schoolers makes me feel really old," said Mr Zuckerberg, 26, who created Facebook in his Harvard University dorm room in 2004.
Around 70 per cent of Facebook's users regularly use it to send messages to friends, with a total of four billion messages passing across the site each day. Its move into email, linking Facebook users to people outside the site, could dramatically increase those numbers.
According to Silicon Valley gossip, Facebook engineers working on the service had nicknamed it the "Gmail killer", in reference to Google's email service. Gmail users – like those of other email services – will be able to access their mail within Facebook from now on, or could decide to switch to a Facebook email address, robbing Google of lucrative advertising. But Mr Zuckerberg played down the rivalry. "They have a great product. Email is still really important to a lot of people."
Anticipating concern from privacy advocates who fear that users are already sharing too much personal data with Facebook, Mr Zuckerberg defended the company's use of targeted advertising. He said it should be less of a privacy concern than other advertising networks who track web users to assemble information about sites they like to visit. "Our ad system is based only on what you put in," he said.