The move follows Facebook's acquisition of FriendFeed yesterday, and the launch of its ramped up search function.
The company, in a statement, said: "We are currently testing a simplified alternative to Facebook.com that loads a specific set of features quickly and efficiently.
"Similar to the Facebook experience you get on your mobile phones, Facebook 'Lite' is a fast-loading, simplified version of Facebook that enables people to make comments, accept Friend requests, write on people's Walls, and look at photos and Status updates."
Including Facebook Lite, a major theme prevails -- real-time.
Over the past few months, Facebook has made subtle changes to its website, aimed at emulating the de facto champion of real-time, Twitter.
In March, it rolled out its real-time homepage, which in many ways looked like a cross between Twitter and FriendFeed.
From this, it began allowing third party developers to create applications from its news feed, something Twitter has benefited from immensely, especially with its desktop clients Seesmic and Tweetdeck, which recently integrated Facebook into its service.
In June it granted users full control over their privacy limitations, which many of taken advantage of, allowing status updates to be broadcast to everywhere on the web, mimicking the public nature behind Twitter.
Its new search function, rolled out yesterday, allows users to search Facebook as they would Twitter, to find trending topics as they happen.
A screengrab of Facebook Lite taken this morning shares similarities with Twitter users' profile pages, with a streaming conversation down the centre, with options to post pictures or videos.
Facebook said the beta test invitations were sent out by mistake, but Facebook Lite should be officially launched soon.
The words "Facebook Lite" is presently topping Twitter's trending topics list.
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