Facebook, a popular social networking site, has come out with an improved messaging platform which aims to provide users with more than just an e-mail application.

The new messaging system envelopes e-mail, instant messages, Facebook messages and SMS to help users communicate faster and more seamlessly with their friends.

Facebook founder Mark Zuckerberg said the site is rolling out a whole new messaging system over the next few months that "isn't just e-mail," but integrates four common ways users communicate on Internet: email, Facebook messages and chat, and SMS, and archives it all in a single thread.

Swatting down recent rumors that he is launching a 'Gmail killer', Zuckerberg at a Facebook event in San Francisco said "This is not an e-mail killer... This is a messaging system that includes e-mail aspects to it."

Zuckerberg said project "Titan", as its service is called, was taken up after high school students, in chats, said they seldom use e-mail because "it's too slow" and "too formal."

The new system puts a user's identity above the communication protocol.

Facebook engineer Joel Seligstein said, "You decide how you want to talk to your friends...They will receive your message through whatever medium or device is convenient for them and you can both have a conversation in real time. You shouldn't have to remember who prefers IM over email or worry about which technology to use. Simply choose their name and type a message."

Messages are received in an inbox, but it eschews the conventions of e-mail and Facebook messaging (subject lines, recipient/cc/bcc fields), and instead turns all conversation into a chat, where the conversations are merged. So, if one is conversing over Facebook chat, then the switches over to a mobile device, the conversation stays in the same place, except it is being sent through SMS.

It currently handles the four different methods of communication, but as it rolls out, it will also become a sharing and collaboration platform.

Microsoft, which holds a stake in Facebook, has announced that it is integrating the Office Web Apps experience into the new messaging system. Users will be able to share Word, Excel, and Powerpoint documents in Facebook messages, and download them to their desktops.

Facebook's new messaging system will be rolled out to different groups of users over the next few months, and will include a new mobile app and @Facebook.com email addresses for interested users. The addresses will be available to all irrespective of the whether they are Facebook users.

Another feature to be added is the 'Conversation History', wherein all messages with someone can be put together in one place, whether they are sent over chat, email or SMS, and can all be seen as a single conversation.

The next feature is the 'Social Inbox', where the Inbox will only contain messages from your friends and their friends, while other messages will be contained in a separate folder. Facebook said in the 'Next Generation' messaging users can just select friends by name and be able to share with them instantly.

Zuckerberg said, approximately 350 million of Facebook's more than 500 million members fire off messages at the service, with more than four billion digital missives sent daily.

With such a large user base, a free personalised facebook.com e-mail service lays down a powerful challenge to the established e-mail giants -- Microsoft's Hotmail, Yahoo Mail and Google's Gmail.

Hotmail currently has the most users -- 361.7 million as of September, according to online tracking firm comScore, followed by Yahoo with 273.1 million and Gmail with 193.3 million.

Facebook's new messaging service comes amid sparring with Google over data sharing. Google this month blocked Facebook from importing Gmail contact information over the social network's refusal to share data about its users.