Twitter on Thursday announced it has finished rolling out overhauled pages crafted to boost the appeal of the message-sharing service to users around the world.

"At the very core there are fewer places you have to click and less you have to learn," Twitter co-founder Jack Dorsey said as he and other executives unveiled the changes at the startup's San Francisco headquarters in December.

"We've done a lot of user testing and it has proven to be much simpler," Dorsey added.

Overhauled navigation features take advantage of the fact that Twitter symbols such as @ and # are making their way into common culture, showing up anywhere from text messages to advertising billboards and television.

Twitter designed Connect navigation tools that essentially turn those symbols into new age URLs, or web addresses, to let people find all posts or other information being fired off about topics.

Twitter also expanded profile pages, letting users tell more about themselves or, in the case of companies, their brands.

Dorsey said revenue from "promoted tweet" style ads has been steadily growing and the startup is easing out a self-service advertising system.

Advertising revenues at Twitter grew 213% to $139.5 million in 2011, up from $45 million in 2010, according to eMarketer.

The market tracking firm predicted that Twitter will bring in $259.9 million in advertising revenue this year, and that the global revenue would hit $540 million by the year 2014.

The Twitter overhaul completed on Thursday includes new Timeline that brings together all Twitter chatter or content related to a particular "tweet."

"There is a universe within every tweet," Twitter chief executive Dick Costolo said at the unveiling. "The 140 characters are a caption associated with a rich canvas that could be a song, a video, a photo or more."

The new Twitter design was described as a platform on which the service will build to reinforce its effort to "reach every person on the planet."

"Of course tweeting is still front and center," Dorsey said. "Any time you have something to tell the world you can do it instantly."

Twitter engineers speeded up the service's engines to deliver content faster, and new tabs at the tops of pages let people jump quickly between Home, Connect, Discover, and Me.

The Connect page lets users search Twitter using the @ sign, which has become Internet age shorthand for "at."

The bottom of the Connect page let people tap on Interaction or Mention tabs that show who is responding or rebroadcasting their tweets.

Discover focuses on searches based on # symbols, which are used at Twitter to label topics such as "#arabspring."

The Home tab leads to the Twitter flow users are familiar with, while "Me" takes people to profile pages.

"We have to provide the simplest, fastest way for people around the world to connect with everything they care about," Costolo said. "This wasn't just a change in the interface; this was a whole company effort.