London, Nov 16 (IANS) Online social networking website Facebook has launched a new messaging service for its 500 million users, predicting the traditional internet communication system email will soon become extinct.

The new system, which integrates all web and text-based communications and works instantaneously, can be used by the social network users through a Facebook.com email address, according to the Daily Mail.

Email is too slow and formal and will eventually follow the letter into extinction, said Facebook founder Mark Zuckerberg.

The service, perceived as a rival to Google's Gmail, is modelled on instant messaging and online chat. Texts, email or instant messages will all come into one "feed" and users can respond in any way they want.

For example, one person could text a friend, who will see the message come up on their Facebook page instantly and respond via an instant message or email.

Entire conversation histories going back years will also be saved into users' accounts and spam will be completely filtered out, Zuckerberg said.

"We don't think that a modern messaging system is going to be email," Zuckerberg was quoted as having said at a press conference in San Francisco. "We want people to be able to communicate in whatever way they choose: email, text or Facebook message."

Currently Facebook users are able to contact each other by either posting on each other's profile page or by Facebook's own internal messaging service.

Zuckerberg said: "It's true people are going to be able to have Facebook.com email addresses but this is not email. Email is one way people are going to use this system, but we don't even think it's going to be primary way that people use this system.

He said that he did not think there would be an overnight e-mail exodus but that young people have "suddenly shifted towards real-time communications" and he had to respond.