Twitter has launched a comprehensive overhaul to the social networking site, including updates to the Web interface, as well as the iPhone, Android and Tweetdeck applications.

The update, dubbed Twitter Fly, features an entirely redesigned Web interface, with each element - where to type a new tweet, "who to follow," trending topics and your timeline - in individual windows.

Twitter announced in a blog post: "Today we introduce a new version of Twitter. We've simplified the design to make it easier than ever to follow what you care about, connect with others and discover something new.

"You'll see this new design both on and mobile phones, so that you'll have a familiar experience any time, anywhere."

The microblogging service has also rolled out an update to Tweetdeck which features a similar new design but, curiously, there isn't yet an update to the official Twitter app for Mac.

Twitter founder Jack Dorsey said the new Twitter means "less places to click, less stuff to learn."

"We are setting the foundation so we can move quickly and most importantly innovate quickly," said Dorsey, who added that this update is "just the first step."

Twitter said it will be rolling out the update over the next few weeks, but the mobile applications and Tweetdeck can be downloaded now.

"We're working on updates for other apps, such as Twitter for iPad, and will share news as they become available.

"What we're announcing today is just the beginning. We now have a framework in place that we will quickly build and iterate upon to help users connect with whatever is meaningful to them."