London, Sep 16 (IANS) Twitter has unveiled its first major revamp since its launch four years ago.

The newly-introduced features make it easier for its 160 million users to view photos and videos.

The new look is designed to tempt users to linger on Twitter's website for longer periods as an incentive to advertisers, reports the Daily Mail.

"We are still figuring out all the new possibilities," Twitter co-founder Biz Stone said.

It is being feared that the redesign is likely to upset users, just as major changes to sites like Facebook had made users angry in the past.

The facelift, expected to roll out worldwide in a few days, splits the website into two panes.

One is devoted to the 90 million messages or 'tweets' posted on the website each day and the other features the images contained within the text.

Until now, most links to photos and videos were displayed on other websites or browser tabs.

The website's left pane will look familiar, featuring a timeline that chronologically stacks all the tweets from the people that users choose to follow.

The right panel appears to open up a new area for content. It is being set up so users can click on individual tweets to look at embedded images and other information without having to navigate away from their home pages.

"It's all about getting more out of Twitter in a lot less time," Twitter boss Evan Williams said.

People are mainly opening accounts now so they can follow the tweets from the friends, family, celebrities, media outlets that interest them.

Research analyst Augie Ray believes the growing volume of spectators is the main reason why Twitter wants to make it easier to wade through the sea of content cascading through its website daily.

Twitter has reached agreements to display content from more than a dozen online photo and video sites, including Google-owned YouTube and Yahoo's Flickr.