Facebook is seeking to extend its reach by allowing other websites to have their content and services promoted more heavily to Facebook users.

The social networking site said that people would be able to log in to other sites using their Facebook account information, and have their activities on those sites broadcast back to their Facebook friends.

Sites which participate in Facebook Connect, which was announced at Facebook's annual developer meeting last night, will not have to ask their users for a separate login and password, and will be able to tap into those users' friends by sending messages via Facebook's 'news feeds'.

The scheme, which was announced by Facebook's 24-year-old chief executive, Mark Zuckerberg, bears similarities to an advertising system the company announced last year called Beacon, which was widely deemed to be invasive because Facebook users did not get a say in whether their activities elsewhere on the web would be broadcast to their friends.

Facebook later apologised for the scheme, and last night Mr Zuckerberg was keen to stress that the company had learnt from its mistake, and would give users full control over the privacy settings which would determine which of their activities would be "shared".

"The power of feeds on Facebook is their ability to move you into a world where you receive relevant information in a social context wherever you are on the web," Mr Zuckerberg said. "I think we are at the beginning of a movement and the beginning of an industry."

He also said Facebook would change the way it distributed applications - the small programs like Scrabulous which third-party developers are free to write and make available to Facebook users - by giving priority to those which stood out as better than others.

The move was interpreted as an acknowledgment that the site had become clogged with applications or apps, as they are known, and that by rewarding some apps with a privileged status - for instance by allowing them to work more closely with Facebook's platform - developers would be encouraged to write better programs.

"As happy as I am with the growth of the eco-system, there are a lot of mistakes we made. I think we can all agree that we don't want an eco-system full of applications that are just trying to spread themselves," Mr Zuckerberg was quoted as saying.

Among the applications to have been singled out for a new "Great Apps" section on the site - which will have give them greater visibility - were iLike, a music recommendation program, and Causes, a charitable giving tool.

But it will be the ability of other sites to tap into the Facebook network which will most interest third parties - particularly advertisers who are keen to explore the potential of so-called "word of mouth marketing", which is effectively what the new scheme will allow.

Among the sites to have signed up to Facebook Connect are Hulu.com, the video streaming site which is a joint venture between NBC Universal and News Corp, parent company of Times Online, the Disney-ABC Television Group, CBS.com, and Twitter, the micro-blogging site.

Facebook is under pressure to increase its revenues, which are not growing as fast as it would like. The company recorded $150 million in sales last year and is hoping to double that figure in 2008 - its fourth full year of operation.

Google, the search giant to which it is often compared, earned $440 million in its fourth year - a five-fold increase on the previous year.

Explore Tech & Web

• Personal Tech

• The Web

• Gadgets & Gaming